Air flow rate into car engine - Page 1
Forum section: electronics / general

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 11:53:18 am
content: I was wondering what the ball park figure was for air flow into a car engine. Mainly at lower engine speeds.The background to this is that I notice that my engine performance is not so good in hot weather, I know that hot air is less dense than cold air so takes up more room and less mixture gets into the engine. So what if it was possible to just take a few C off the air with say a peltier cell ? This is all wild speculation and I'm not particularly in a hurry to make anything. I have a diagnostic reader, would the value of air flow be in the diagnostic data ?The other way of finding out would be if anyone knows the mix ratio of air and petrol in the engine as I know the petrol consumption.

author: darrylp
author_rank: Regular Contributor
timestamp: July 25, 2012, 12:02:11 pm
content: Air flow reading from OBD2 data port I'm not sure.Getting an air to air inter cooler would help (go look at turbos which use them. Cheap second hand is possible here) air fuel is normally in UK 14.7 of air to 1 of fuel. Go read about lambda. Modern carbs will lean burn. Ie even more air for one unit of fuel. I've heard up to 20:1 being used.Sent from my HTC Desire using Tapatalk 2

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 12:04:43 pm
content: no, air to air will not help (I work for a radiator company). I am trying to cool ambient air to below ambient. Inter-coolers are used to cool compressed air in Turbo systems back down to ambient after it has heated up in a compressor.

author: Psi
author_rank: Super Contributor
timestamp: July 25, 2012, 12:15:39 pm
content: Quote from: Simon on July 25, 2012, 11:53:18 amI wouldn't have thought the difference in air temp on a hot vs cold day was big enough to cause noticeable performance changes.If you can notice a difference then i expect there is some other problem. Perhaps a faulty temp sensor is preventing the car from running efficiently in hot weather.

author: grumpydoc
author_rank: Super Contributor
timestamp: July 25, 2012, 12:20:19 pm
content: QuoteI'd be inclined to agree, however reduced pressure with altitude is enough to noticably change performance.Don't modern car engines have an air mass sensor anyway?Presumably you can work it out from engine displacement, no of cylinders and RPM.

author: Psi
author_rank: Super Contributor
timestamp: July 25, 2012, 12:28:12 pm
content: Quote from: grumpydoc on July 25, 2012, 12:20:19 pmYeah, anyone who wants to see just how much pressure changes performance should watch the Top Gear Bolivia Special. It's one of their best specials imho.

author: Rerouter
author_rank: Super Contributor
timestamp: July 25, 2012, 12:35:58 pm
content: personally i doubt it would be from the airs lower density, considering your fuel becomes less dense at a fairly similar rate when you take into account the mixing ratio,i suppose it comes down to how drastic the change in performance is,

author: Baliszoft
author_rank: Frequent Contributor
timestamp: July 25, 2012, 12:38:33 pm
content: I think freezing the air (to get some performance yield) would require too much energy. It is something like generating H2 on the fly.BTW: there are water/air coolers which can be filled with ice cold water (or with cooler substance), but they are mostly used for drag racing (for just a fraction of a minute) on forced induction engines.The airflow on a 2L engine is usually between 3g/sec (idle) and 50 g/sec (part throttle) and as other members wrote, the air fuel mixture is mostly 14.7 parts air : 1 part fuel for gasoline.

author: GK
author_rank: Super Contributor
timestamp: July 25, 2012, 01:08:23 pm
content: Quote from: Psi on July 25, 2012, 12:15:39 pmNoticable in just about any car and definately measurable on the chassis dyno. In fact for this very reason the most state of the are dyno booths are air conditioned / climate controlled. Cold air is denser, so a greater volume enters the cylinders and makes a bigger bang.

author: vk6zgo
author_rank: Super Contributor
timestamp: July 25, 2012, 02:26:37 pm
content: "Cold air packages" were a very common concept with modified cars back in the 1960s/70s.The idea was that the air normally "breathed"from the area under the bonnet/hood of the vehicle was already heated,with resultantlower density.This was the original motivation for the plethora of "scoops,"etc which made their appearance in that era.As another poster said,the air mass sensor in modern cars should obviate any requirement for cooler air.

author: GK
author_rank: Super Contributor
timestamp: July 25, 2012, 02:34:13 pm
content: Quote from: vk6zgo on July 25, 2012, 02:26:37 pmThat doesn't make any sense.BTW, cold air intake kits were not just a 70's fad - they are fitted to every current HSV and FPV just for example and every 2nd ricer is sticking pod filters from anywhere from next to the headlights to actually in the front wheel wells in a attempt to get around sucking hot air from under the hood.

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 02:35:44 pm
content: Cars definitely perform better on cold days. The effect is or should be rather less noticeable in vehicles with a modern engine management system because the system can compensate for the changes in air density.I know how to calculate the air flow but I can't give you a number this instant. Maybe later when I have free moment. What is the fuel consumption you have?

author: GK
author_rank: Super Contributor
timestamp: July 25, 2012, 02:47:17 pm
content: Quote from: IanB on July 25, 2012, 02:35:44 pmActually it’s generally the other way round. Modern EFI makes it possible to maintain stoichiometric metering even on a very cold morning with freezing cold air, thus taking full advantage the much denser (colder) intake charge.

author: firewalker
author_rank: Super Contributor
timestamp: July 25, 2012, 02:49:50 pm
content: Yep,intercoolersare quite common these days.Alexander.

author: SeanB
author_rank: Super Contributor
timestamp: July 25, 2012, 03:03:35 pm
content: More bang for the buck would be to add a water mister to the inlet airflow. This does increase power output a lot, and is often used to increase power.

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 03:05:30 pm
content: Quote from: GK on July 25, 2012, 02:47:17 pmI see your point. I meant to say that the performance degradation experienced on a hot day or at higher altitudes would be less marked in a modern vehicle than in an older vehicle with a carb.

author: Rufus
author_rank: Super Contributor
timestamp: July 25, 2012, 03:06:37 pm
content: Quote from: Simon on July 25, 2012, 11:53:18 amIf peltier coolers were efficient and economical they would use them for air conditioning. What to EVs do for air con? Having only an electrical primary energy source and not much concern for cost I would think them the ideal candidate for peltier air con if it were at all viable.I seem to recall some Volvo race (touring) cars having a refrigeration pack providing chilled water to the inter-cooler.Some high performance turbos have water sprays on the inter-cooler to loose a bit more heat to evaporation.

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 03:10:50 pm
content: Quote from: Simon on July 25, 2012, 11:53:18 amIt's usually much more effective to compress the air with supercharger or turbocharger. That's why high performance vehicles go this way.It would take a lot of energy to cool the air flow down enough to make a difference, and I would hazard a guess that the costs would exceed the gains.

author: vk6zgo
author_rank: Super Contributor
timestamp: July 25, 2012, 03:42:21 pm
content: Quote from: GK on July 25, 2012, 02:34:13 pmMy point was that with a carby you never get anything but a compromise mixture,whereas the air mass sensor is one of the inputs to the ECU,which can then adjust to the bestpossiblemixture.Many of us used to sneer at Cold air packs back in the day,but they apparently worked.Superchargers were expensive in those days,plus were not always allowed for some categories of competition.

author: G7PSK
author_rank: Super Contributor
timestamp: July 25, 2012, 04:09:35 pm
content: Most cars will run better when its raining but if there is a noticeable drop in performance on a hot day I would look at the engine cooling is the radiator working properly has it been flushed out recently, I once had a car from the London area and the radiator and engine water jacket was packed with what looked like red mud that was so hard it had to be chipped out of the engine in order to remove it and the radiator was a write off. If the radiator or fan is the problem you check and see what happens when you put the heater on full blast this will often cool the engine considerably.

author: dbinokc
author_rank: Contributor
timestamp: July 25, 2012, 04:23:18 pm
content: Where changes in air temperature are really noticeable is if you fly an airplane. On a really cold day, my Cessna 152 would feel like a rocket compared to its performance on a really hot day.The way pilots take into account air variations with temperature is density altitude. In simple terms, this is a value that basically allows you to know how your aircraft will perform. Higher density altitudes mean less performance for the engine, propeller and wing. Especially on takeoff. If the density altitude is too high, you will run out of runway before you get off the ground. Many planes have crashed on takeoff because the pilot did not account for this.

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 04:40:22 pm
content: Quote from: firewalker on July 25, 2012, 02:49:50 pmThat is entirely a different matter as I'm not talking turbo charged engines. Yes they are very common, from the shittiest little Lotus to military tanks, they all have them and I work with them all.

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 04:47:47 pm
content: Quote from: Simon on July 25, 2012, 11:53:18 amYou first of all might want to check the efficiency of your cooling system. Although engines in principle run more efficiently when they run hotter, there are practical considerations in that higher engine temperatures may lead to misfires and uneven running. You would notice this more at low speeds than at high speeds.So check the condition of the radiator, make sure the thermostat is working right, and see if your cooling system may need flushing. Look at the temperature gauge and see if it gets further towards the red than normal.Also, check the adjustment and operation of the ignition system. The first and most common cause of poor running in a car is something wrong with the timing or ignition.

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 04:51:14 pm
content: There is nothing wrong with the engine. It just passed the MOT test and that involved them having a look at it as the lambda sensor readings were all out due to a hole in the exaust.The difference between hot and cold is slight, but i notice it and have done on the last 3 cars I have had, I am not heavy on the throttle so feel the engine and what it is doing with what I give it. I average a consumption of 10 miles/L. It is a 1.3L engine.What was someone saying about a mist spray ? Another option might be to put a blower on the air intake to force a bit more air in ? I notice the performance change mostly on pull away which will be when the engine is under most load and i guess a denser mix makes a bigger bang and more acceleration. If I'm having to accelerate and make the engine go faster to compensate I'm going to use more fuel. My rad is ok, the coolant normally normalizes at 85C and the thermostat kicks in at about 92C and then the temperature drops within seconds to 85C.The other thing I notice is that if I shove my foot on the throttle, I don't neccesarily use that much more fuel but the car can pick up speed quite easily, maybe the throttle can hinder the mix getting in fast enough ? I'm not bothered by this just something I notice on my diagnostics display that may even be reading that wrong.

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 04:52:48 pm
content: Quote from: IanB on July 25, 2012, 04:47:47 pmEngine runs quite smoothly

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 04:53:21 pm
content: The density of air at 15 C/60 F is about 6% greater than the density of air at 32 C/90 F, so all things being equal a car would have about a 6% greater maximum power output on the 15 C day. However at lower speeds it wouldn't be too hard to compensate for this by adjusting the throttle position. So I don't think you could easily tell unless under flat out acceleration.

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 04:58:01 pm
content: We are cross-posting but it sounds like you do notice the effect more under acceleration. I guess with a smaller 1.3 L engine the differences will be more pronounced than with a bigger engine.The job of the throttle is to literally throttle the air flow. So one way to get more performance out of an engine is to provide a bigger path for the inlet air. Bigger air intake, bigger, lower resistance air filter, wider throttle body, etc. Standard engine tuning stuff. Dunno if you want to go that far...?

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 05:12:19 pm
content: Quote from: IanB on July 25, 2012, 04:58:01 pmnope, blower on the intake is as far as I'd go.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 25, 2012, 05:26:56 pm
content: A blower on the inlet will never work, have a Google for 'surbo' and the tests done. To move the amount of air that an engine needs would take a huge amount of energy.The best way, as already mentioned, is with water injection. I have an aquamist kit here which I was going to use on one of my old cars (that I added a turbocharger to)A water to air chargecooler will also give temps under ambient but the restriction on the inlet will reduce flow far more than denser air will increase.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 25, 2012, 05:28:53 pm
content: Actually surbo is something else, the name of the actual electronic turbo escapes me now

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 05:30:40 pm
content: Quote from: Chet T16 on July 25, 2012, 05:26:56 pmhow do you make the water colder than ambient. cac's have high flow rates due to big connections and large tubes in the radiator core

author: IanB
author_rank: Super Contributor
timestamp: July 25, 2012, 08:01:24 pm
content: Here are a few back-of-the-envelope estimates.Firstly air flow.Assume the car does 40 mpg at a steady 60 mph.Fuel rate will be 60 mph/40 mpg = 1.5 gal/hConvert to litres per hour:1.5 gal/h x 4.55 l/gal = 6.8 l/hAssuming petrol density is 0.74 kg/l6.8 l/h x 0.74 kg/l = 5.1 kg/h of fuelFor air flow, use a nominal air/fuel ratio of 14.7.Then the air flow will be 5.1 x 14.7 = 75 kg/h = 21 g/sNext, cooling requirement.Suppose we want to cool the air by 15 degrees C.The specific heat capacity of air is approximately 1 J/g/degC.To cool the air by 15 degrees the heat load is therefore:21 g/s x 1 J/g/degC x 15 degC = 300 WSo you would need approximately 300 W of thermal cooling duty, more under acceleration.Lastly, water injection.Suppose you wanted to increase the air density by 5% corresponding to a 15 degree cooling effect.This means you need to inject 21 x 0.05 = 1 g/s of water at the inlet manifold, or 0.06 l/min.(We can neglect the volume of the water droplets compared to the volume of the air.)What I expect to happen is that the water vaporizes inside the engine producing steam of much greater volume.So a water spray turns the internal combustion engine into a kind of hybrid steam engine.Looking at the numbers, the water spray seems to be a somewhat effective way to get a performance increase out of an internal combustion engine.

author: Simon
author_rank: Unknown
timestamp: July 25, 2012, 09:10:32 pm
content: very interesting, Thanks. So how does this water thing work ?

author: Zad
author_rank: Super Contributor
timestamp: July 25, 2012, 11:59:24 pm
content: For goodness sake don't go anywhere near those "electric superchargers". At best they throttle the existing airflow. At worst, the fan blades break up under overspeed conditions, and cause the valves to not close, resulting in the pistons hitting them and a bill for a new cylinder head, conrods and crank shaft. If you get one, I'll send half of Pistonheads round your gaff to point and laugh at you. To compress air to any noticeable effect takes a HUGE amount of power. Even a modest supercharger takes around 10% of the engine's power. Say 10bhp, or 7500W.Water injection is well documented. Mostly in relation to forced induction, but it has an effect on normally aspirated engines too. Usually a mixture of water and ethanol is injected at pressure under load, atomising to form small droplets. The massively greater surface area enables the water to evaporate to gaseous form, extracting energy from the air around it. This has the obvious effect of chilling it and making it more dense. It also acts as an octane improver and moderates the flame front, with the result that modern engines with active knock detection can advance the spark further and increase performance. The ethanol is mainly there to stop the water icing, rather than for an energy boost.Early Saab Turbos used to have a button to inject water from the screen washer bottle.http://en.wikipedia.org/wiki/Water_injection_%28engines%29

author: IanB
author_rank: Super Contributor
timestamp: July 26, 2012, 12:35:49 am
content: Quote from: Zad on July 25, 2012, 11:59:24 pmYou got me curious, so I looked at this with similar numbers to my example above.If we say the air flow is 75 kg/h at an ambient temperature of 20 C and we want to compress it to a 10% increase in density with an efficiency of 85%, then I calculate that the power requirement would be 300 W (0.4 hp) and the air temperature would increase to 35 C after compression (no aftercooler probably needed). The pressure boost in this case would be 16 kPa or 2.3 psi.This would be a very mild boost giving a very moderate performance increase, but equally would be much simpler to arrange then a typical "real" boost of 10-15 psi.Of course the assumed air flow would be greater under acceleration than under 60 mph cruising. And the mechanical complexity for a small boost like this might not be worth it. Although this is where perhaps an electrical supercharger might be more relevant than a mechanical or turbo booster.(Note: I used a simulation tool to avoid crunching the numbers, so no working shown.)

author: Zad
author_rank: Super Contributor
timestamp: July 26, 2012, 02:43:13 am
content: I'm sure the OP keeps his car serviced on the dot, as per manufacturer's schedule, but deterioration does occur which reduces the overall system efficiency. Regular services and checks can only go so far and tend only to detect major failures. For example, the catalyst may gradually block up over a time, increasing back pressure and reducing flow. Air mass metering (depending on method) may deteriorate; hot wire sensors corrode and coke up, vane flow meters wear out, and hoses connecting pressure sensors can deform, clog up with dirt and leak imperceptibly. Engine management units do adapt, but there is only so much they can do without calibration versus known standards. There is nothing they can do to adapt around a blocked catalyst or an exhaust which has degraded wadding in the silencer chambers, a HEGO (oxygen) sensor or engine coolant sensor.Any electric fan would only be good for low boost pressures at low flow rates. The more conventional method of avoiding the installation of a large fan and motor is more commonly known as "putting your foot down a bit". Many new cars are now fly by wire, and don't directly operate a throttle linkage. The effect of warmer less dense air should be taken out of the equation as the engine management unit automatically opens the throttle a bit more to supply the demanded power.

author: GK
author_rank: Super Contributor
timestamp: July 26, 2012, 06:35:56 am
content: Quote from: Chet T16 on July 25, 2012, 05:28:53 pmTurboZet!Autospeed magazine did a write up. Totally ridiculous concept.

author: T4P
author_rank: Super Contributor
timestamp: July 26, 2012, 09:28:00 am
content: Surbo, as it is called is not the electronic superchargersBut rather something called a "suction turbo" and it talks more then it promises ... it basically creates a vortex but there's the risk of impeded airflow

author: dcel
author_rank: Regular Contributor
timestamp: July 26, 2012, 04:41:44 pm
content: For a cooler intake charge look up water-meth injection. Most of the diesel heads here use it to cool charge air, but I have seen and drove it on carb and EFI vehicles and it works. The secret is the methanol. I drive a dodge cummins turbo diesel and changes in air temp, humidity, and pressure are very noticeable in driveablity. What is your average ambient temp there Simon, has it been hotter and muggier than normal?Chris

author: Simon
author_rank: Unknown
timestamp: July 26, 2012, 04:50:43 pm
content: well we have had a month of non stop rain then baking heat that I bet is humid due to the water evaporating out of the ground. Now I see a difference.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 26, 2012, 04:58:26 pm
content: i'm not the expert. but maybe? since the hotter day, cooling system needs to work harder to cool the coolant. water pump need to ON most of the time, radiator fan as well, and those need electricity and power to pump and alternator, hence fuel consumption? as for combustion energy, i believe the ECU or our foot will compensate? and temp diff is doesnt matter as its hell hot inside the block, winter or sunny, no?

author: Simon
author_rank: Unknown
timestamp: July 26, 2012, 05:08:11 pm
content: The engine block is maintained at 85C it will be hotter in the cylinders, I have this monitored on my diagnostics panel. The water is always pumped round by the engine on a mechanical pump, providing the car is moving the radiator fan will not need to come on.

author: Simon
author_rank: Unknown
timestamp: July 26, 2012, 09:27:24 pm
content: I'm surprised that with all these do it yourself kits no one has come up with a small compressor system. Those cheap 12V compressors are like a fiver now so you could even run 2-4 in shifts or some other more efficient device could be used. Fans are really not the best things at pumping air through pipework and the pressure gains of fans are minimal.I think the thing is ultimately the air flow is due to the engine having to physically suck the air in rather than it be delivered, in fact this explains why if i open the throttle more the petrol consumption does not massively go up but the car accelerates. Surely it makes sense for the air to be "put in" to the injection system rather than the engine be sucking the air in all the way through the injector and air filter.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 26, 2012, 09:34:41 pm
content: I think you're really underestimating the volume of air needed!

author: Simon
author_rank: Unknown
timestamp: July 26, 2012, 09:47:07 pm
content: Quote from: Chet T16 on July 26, 2012, 09:34:41 pmQuite possibly, most compressors are made to pump up to 7-10 Bar (well so they claim), something that moved more air but no more than 1 bar would do the trick.

author: IanB
author_rank: Super Contributor
timestamp: July 26, 2012, 09:53:14 pm
content: Quote from: Simon on July 26, 2012, 09:27:24 pmYes, but look at the numbers.In my example above I chose a really low air flow for a small car in 60 mph cruising (limited throttle, no acceleration), and I chose a very mild level of turbo boost (about 2 psi).If we look at the calculation, that required 300 W, or about 25 A from a car electrical system. And the air flow of 75 kg/h corresponds to about 36 cfm.Comparing to shop air compressors, 36 cfm is quite large. A little cheap 12 V thing won't cut it.If you start looking at larger air flows and higher boost pressures you quickly get above 1 kW power requirements.It's not so easy to do this electrically.

author: IanB
author_rank: Super Contributor
timestamp: July 26, 2012, 10:01:45 pm
content: Here are two examples. The first is for low air flow and mild boost. The second for a much larger air flow and significant boost. Note how the second one needs 2.6 kW of power and makes the air quite hot, so an aftercooler would be needed before feeding the air to the engine.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 26, 2012, 10:06:53 pm
content: I wonder how much power it would be for my integrales 30psi!

author: Baliszoft
author_rank: Frequent Contributor
timestamp: July 26, 2012, 10:10:33 pm
content: Quote from: Simon on July 26, 2012, 09:27:24 pmElectronic superchargers could not make it (until the present history). Not coincidentally. A 150HP engine pushes nearly half a ton of air through itself in an hour.

author: Baliszoft
author_rank: Frequent Contributor
timestamp: July 26, 2012, 10:11:32 pm
content: Quote from: Chet T16 on July 26, 2012, 10:06:53 pmHundreds of amps probably.

author: Unknown
author_rank: Unknown
timestamp: July 26, 2012, 10:22:59 pm
content: It would be interesting to see how ambient temperature throws the results. Say from -20 to +60 (under bonnet).

author: Zad
author_rank: Super Contributor
timestamp: July 26, 2012, 11:20:15 pm
content: A modest (but real world) 10hp supercharger would require 625 Amps. A higher powered engine with, say 50% more power, would double the power requirement. Good luck generating 1250A.

author: IanB
author_rank: Super Contributor
timestamp: July 26, 2012, 11:45:26 pm
content: Quote from: Chet T16 on July 26, 2012, 10:06:53 pmTo do that we need an estimate of the air flow. I'm looking for a number for the fuel efficiency of a typical engine. One number I found was 240 g of petrol per kWh of output, but I'm looking for more data for verification. Apparently engine dynamometer charts give this info. Any petrolheads got an example? Once we have this we just have to go with the power output of the engine and we can figure the fuel flow and the air flow from that.Wikipedia says the 1.9 Twinturbo Multijet 16V Integrale develops 190 hp.

author: IanB
author_rank: Super Contributor
timestamp: July 26, 2012, 11:50:10 pm
content: Quote from: HAL-42b on July 26, 2012, 10:22:59 pmSee below. High ambient temperatures significantly increase the power requirement on the compressor for the same boost.Edit: This is not strictly true. It is more realistic to maintain the same volumetric air flow rather than the same mass air flow. In this case the power requirement doesn't vary so much.

author: Unknown
author_rank: Unknown
timestamp: July 26, 2012, 11:57:53 pm
content: Toyota and Ford are both developing workable electric supercharging. (I gave up looking for the Toyota one after googling 10 pages of fan in pipe junk. Here is the Ford offering which proves that no you cannot change the laws of physics, with the supercharger achieving small amounts of boost by helping to spin up a too big turbo on a too small engine.http://news.drive.com.au/drive/motor-news/fords-electric-supercharger-20120703-21esd.htmlSimon the small high volume compressor falls into the same capacity as the compact lightweight high delivery battery, both would be revolutionary if only they existed and more importantly were available at low cost.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 27, 2012, 12:06:04 am
content: Quote from: IanB on July 26, 2012, 11:45:26 pmI did have it on a dynamometer but the chart went when i sold the car. It made 219 bhp at 15 psi and 241 at 20 psi. It was running on 95RON petrol at the time so that was as much boost as i could run. This was a '91 HF Integrale 16V

author: Unknown
author_rank: Unknown
timestamp: July 27, 2012, 12:08:41 am
content: Quote from: IanB on July 26, 2012, 11:50:10 pmThanks. Not as much increase in pumping energy as I expected but 131 degrees inlet manifold temp is not pretty.

author: IanB
author_rank: Super Contributor
timestamp: July 27, 2012, 12:13:11 am
content: Quote from: HAL-42b on July 27, 2012, 12:08:41 amNote that I did that calculation with the same mass flow of air in each case, which is not realistic. I have fixed it to keep the same volumetric flow and now the power requirement doesn't change. However the mass flow changes a lot, which corresponds to a significant loss in engine power in the hot conditions.

author: GK
author_rank: Super Contributor
timestamp: July 27, 2012, 12:18:21 am
content: Quote from: IanB on July 26, 2012, 11:45:26 pmFuel efficiency is irrelevant. All you need is the engines displacement, the RPM and a fair estimation of the volumetric efficiency.I did mention the TurboZet and the associated Autospeed article:http://autospeed.com/cms/title_The-Twin-Turbo-Zet/A_110827/article.html

author: IanB
author_rank: Super Contributor
timestamp: July 27, 2012, 12:52:40 am
content: Quote from: GK on July 27, 2012, 12:18:21 amNot irrelevant, just a different way of getting at the answer. But you are right, the RPM and volumetric displacement does give an alternative route to the information needed. In this case you would need to know the RPM and volumetric efficiency at the conditions of maximum power output, and also the actual boost pressure at the air inlet valves (which will be lower than the turbocharger outlet pressure)--especially if the throttle isn't wide open.For estimates, these nuances won't matter too much.If we happen to know the fuel rate at maximum power and the fuel/air ratio, then we directly get the mass flow of air without going round the houses.

author: Unknown
author_rank: Unknown
timestamp: July 27, 2012, 12:59:30 am
content: Quote from: IanB on July 26, 2012, 11:45:26 pmFor aspiratedhttp://www.csgnetwork.com/cfmcalc.htmleg: 5L at 7500 rpm = 662 CFMWith boost the calculation takes on an variable try here.http://www.lovehorsepower.com/joomla/index.php?option=com_content&view=article&id=35:compressor-flow-map-calculator&catid=8:mr2-helpful-stuff&Itemid=49Same engine at 6psi boost = 840 CFMThe calculationCFM = L x RPM x VE x Pr / 5660Where L = engine capacity in litersRPM = maximum engine speed (we'll adjust this later)VE = engine volumetric efficiency.Stock 2-valve = 85%Stock 4-valve = 90%Street modified = 93%Competition = 105%Pr = pressure ratioTo calculate the pressure ratio you need to know what boost pressure you want to run and then plug that into the following formula:Pr = 14.7 + Boost / 14.7Guestimates abound!!!

author: Unknown
author_rank: Unknown
timestamp: July 27, 2012, 01:03:06 am
content: Quote from: IanB on July 26, 2012, 11:45:26 pmThis happens to be one of the best documented engines out there.Here are a few bits from Guy Croft'sModifying and Tuning FIAT/Lancia Twin-Cam Engineshttp://www.guy-croft.com/(I used to have an old Fiat)

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 27, 2012, 01:03:32 am
content: But isn't that assuming you have a stoichiometric mixture when generally you won't, especially for a turbocharged engine.FWIW max power on the integrale was at ~5700 rpm and the pressures were measured at the inlet manifold.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 27, 2012, 01:04:48 am
content: Quote from: HAL-42b on July 27, 2012, 01:03:06 amThe 1.9 there, is actually a diesel (yuck) A shame for it to have the integrale name!

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 27, 2012, 01:08:48 am
content: Oh, just found this too

author: Unknown
author_rank: Unknown
timestamp: July 27, 2012, 01:12:51 am
content: It's a petrolhead thread nowCongrats on the nice Llancia.

author: GK
author_rank: Super Contributor
timestamp: July 27, 2012, 01:18:55 am
content: Quote from: Chet T16 on July 27, 2012, 01:03:32 amNo.Quote from: Chet T16 on July 27, 2012, 01:03:32 amThe engine I bolted together for my 1300 kg daily hack does >300hp at the wheels at the same RPM with no forced induction on LPG.And that is with a choking 3.5psi of exhaust back pressure. I really need to ditch the single 3" for a twin 3".

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 27, 2012, 01:22:37 am
content: Quote from: HAL-42b on July 27, 2012, 01:12:51 amThanksBut its gone about a year nowGetting an education isn't cheap and it had to go!About time there was a petrol head thead too!QuoteWhat car is this?

author: GK
author_rank: Super Contributor
timestamp: July 27, 2012, 01:27:17 am
content: OK, I confess, not a fair comparison.The stroker kit brought the displacement out to 6.3L.

author: Unknown
author_rank: Unknown
timestamp: July 27, 2012, 01:32:04 am
content: Quote from: Chet T16 on July 27, 2012, 01:22:37 amAn Aussie one. Here's a few minor mods on a stocker Falcon s/c 5L .And we just get the US throwbacks

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 27, 2012, 01:37:49 am
content: Quote from: GK on July 27, 2012, 01:27:17 am50 bhp/litre? Have you tried running it on something that burns? :p

author: GK
author_rank: Super Contributor
timestamp: July 27, 2012, 01:45:36 am
content: Quote from: Chet T16 on July 27, 2012, 01:37:49 amAccounting for tyre friction on the dyno rollers, auto trans dissipation in 2nd and other driver train losses it's closer to 64 hp per litre. It would be in the order of 20% better on petrol instead of the dedicated gas setup, but doing ~350 kilometers per week I prefer 58c per litre to 140c per litre.Also, LPG is cleaner burning. I'm a greenie.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 27, 2012, 02:07:49 am
content: Quote from: Simon on July 26, 2012, 05:08:11 pmhow can you be sure? what "test distance" we talking about? ps: ferrari is fanless radiator thoughQuote from: Simon on July 26, 2012, 09:27:24 pmmaybe its time to provide your car model and test procedure details.is your car VVt-i/VTec/i-DSi/dvvt capable?

author: Simon
author_rank: Unknown
timestamp: July 27, 2012, 09:52:55 am
content: Quote from: Mechatrommer on July 27, 2012, 02:07:49 amI'm sure, I know radiators, I work for the company that makes radiators. The car is a ford fiesta with a 1.3L engine (not a duratec/zetec)

author: Simon
author_rank: Unknown
timestamp: July 27, 2012, 10:12:22 am
content: So do these "extra performance" filters make any difference ?

author: dcel
author_rank: Regular Contributor
timestamp: July 27, 2012, 10:54:38 am
content: Got Boost?Get a turbocharger Simon

author: G7PSK
author_rank: Super Contributor
timestamp: July 27, 2012, 11:23:08 am
content: Put an engine from a VW touran into your car the one on mine has both a turbo charger and a supercharger the same engine is used in a whole range of VW cars not sure if they all have the twin charge but many do.

author: SeanB
author_rank: Super Contributor
timestamp: July 27, 2012, 03:03:18 pm
content: Simon, in a word - no. Most pull air from above the engine, where it is hottest. The oem unit is normally pretty good.

author: IanB
author_rank: Super Contributor
timestamp: July 27, 2012, 04:13:37 pm
content: Quote from: Simon on July 27, 2012, 10:12:22 amIt depends. One of the standard tuning approaches is "air flow", which basically involves reducing the pressure losses in the air intake system as much as possible. One pressure loss occurs across the air filter, so replacing the stock filter with a bigger, easier flowing filter might give a performance improvement. If it's done right and is not fake offering. And how much improvement you might get is debatable. It might be too little to notice.

author: T4P
author_rank: Super Contributor
timestamp: July 27, 2012, 04:15:37 pm
content: Quote from: Uncle Vernon on July 27, 2012, 01:32:04 amOne of the holdens right? I assume it's a standard monaro?

author: Bloch
author_rank: Unknown
timestamp: July 27, 2012, 07:42:07 pm
content: Quote from: Simon on July 27, 2012, 10:12:22 amNo. Only if want a "better" sound.

author: dcel
author_rank: Regular Contributor
timestamp: July 27, 2012, 07:44:00 pm
content: Quote from: IanB on July 27, 2012, 04:13:37 pmAgreed! Get yourself a K&N airfilter, it will make a difference.Chris

author: Bloch
author_rank: Unknown
timestamp: July 27, 2012, 07:52:24 pm
content: Quote from: dcel on July 27, 2012, 07:44:00 pmThere is one problem with K&N airfilter. It is not a "dry" but a "oil" airfilter. And that can and some time will destroy the Air mass measurement sensor.

author: Unknown
author_rank: Unknown
timestamp: July 27, 2012, 11:23:55 pm
content: Quote from: DaveXRT on July 27, 2012, 04:15:37 pmHis probably is! Mine definitely isn't!Say No to low displacement!

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 28, 2012, 12:07:44 am
content: Pfft between me and my brothers we have between 75 and 1048 bhp and the biggest engine is 3.8 and 6 cylinders.Say no to permanent turbo lag, boost wins!Although I have to admit my current project is an NA transplant on throttle bodies...Say no to non european cars :p

author: GK
author_rank: Super Contributor
timestamp: July 28, 2012, 07:42:05 am
content: Quote from: DaveXRT on July 27, 2012, 04:15:37 pmNo! He said Foulcan!These things weigh about 3000 kilos and have the most tail happy real axle you could imagine. I recently caned one of the latest examples with the new "Coyote" super charged 5L. And I thought my VK had traction issues at WOT from stand still! Ha!

author: GK
author_rank: Super Contributor
timestamp: July 28, 2012, 08:01:14 am
content: Quote from: Chet T16 on July 28, 2012, 12:07:44 amWhat is the 1048 hp in?I got 100hp/litre from my Nissan L28 six spinning 7500 rpm, with a set of triple dcoe. That engine is currently out of the car. While I get another project out of the way I am procastinating over rebuilding with forged pistons and injecting and turocharging the six or just plonking in a GM LS3 crate engine.

author: Bloch
author_rank: Unknown
timestamp: July 28, 2012, 09:08:51 am
content: Quote from: Chet T16 on July 28, 2012, 12:07:44 amWhy not more power of such big motors ?VW 1,8L / 4 cylinders 1013PS and 891NmHere on dynoHere on an airstrip0-100kmh in 2,18s0-200kmh in 5,53s0-270kmh in 9,07sweight: 1135kg (2502lbs)

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 28, 2012, 11:00:03 am
content: That golf is awesome! Is it yours?The 1048bhp is an e30 BMW with m5 3.8. I'll post some pics when I'm not using my phone.

author: Bloch
author_rank: Unknown
timestamp: July 28, 2012, 11:41:18 am
content: Quote from: Chet T16 on July 28, 2012, 11:00:03 amNo. And I dont have the skill to build/drive it.Quote from: Chet T16 on July 28, 2012, 11:00:03 amThat is a nice car. The design is best looking BMW. And from a time there was not to much technology in them.

author: T4P
author_rank: Super Contributor
timestamp: July 28, 2012, 04:43:42 pm
content: Quote from: Uncle Vernon on July 27, 2012, 11:23:55 pm6.3L isn't exactly lowOh.

author: Unknown
author_rank: Unknown
timestamp: July 29, 2012, 01:13:13 am
content: Quote from: GK on July 28, 2012, 07:42:05 amWeighs a little less than the GM alternative actually, even before those get plastered with the mandatory 100kg of Taiwanese Chev badges and RIP Brockie stickers. As the pilot of a "Povvo Pak,Blacktown edition VK special on barbecue fuel" you've probably never before experienced HP actually making it to the rears!Many of the Red army confuse lit up rears with torque. Torque is the stuff that makes real cars go quick. Smoke does nothing for your quarter time.

author: Unknown
author_rank: Unknown
timestamp: July 29, 2012, 01:17:40 am
content: Quote from: GK on July 28, 2012, 08:01:14 amA common scenario, did you learn anything from the experience?QuoteCould be starting to catch on..

author: Unknown
author_rank: Unknown
timestamp: July 29, 2012, 01:31:40 am
content: Quote from: GK on July 29, 2012, 01:04:38 amThat golf is modified beyond recognition and around 3 seconds shy of what a blown eight can do. If they could put the HP down and keep the pilot coherent, there would probably be another 2 seconds to be had.

author: GK
author_rank: Super Contributor
timestamp: July 29, 2012, 03:18:40 am
content: Actually the VK does a reasonably good job at putting the power to the ground (in the dry), now that I have a set of decent 235 soft compound tyres and a limited slip diff. However the torque off idle from the very mildly cammed (228 deg at 50 thou) VN headed 383 can still be difficult to manage from a standstill. I was of course exaggerating about the weight of the Foulcan, but going up against one I was genuinely surprised at how bad it was in comparison. The VK does lazy 12's down the quarter. That is on the BBQ fuel with a stock stall converter and factory ratio diff gears. I built it to be a tractable daily hack, not a drag car or hp hero.A stock, base spec LS3 does 440hp. My worked L28 will do that in the '74 Zed with a modest amount of boost but with slightly less overall weight. I'd probably aim for the 450 hp mark. Anything more in a street driven car just pushing past 1000 kg with 225mm tyres is waste of time, IMO. I prefer an overall package that is drivable with tractable power that is usable, rather than something to masturbate over in the dyno booth.

author: IanB
author_rank: Super Contributor
timestamp: July 29, 2012, 03:44:34 am
content: I used to drive one of these:Completely stock, 1.8 litre normally aspirated. And the engine stays in the car and doesn't blow up.OK, so it's not the fastest thing on the road, but sometimes fun trumps ultimate performance.I was quite sad when I had to sell it on moving to America.

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 07:54:13 am
content: I drive a 1.4l Polo, not a racing car. I did drive once with a guy who did 120km in one hour. Pretty impressive considering that was through a mountain pass which normally took closer to 2 hours to do. the car was a mostly stock standard Golf GTI mk 1, and there were 4 of us in the car.

author: Stephen Hill
author_rank: Regular Contributor
timestamp: July 29, 2012, 10:58:47 am
content: Quote from: Simon on July 27, 2012, 09:52:55 amSo which engine is it? I used to have a 1.3 8v Duratec Rocam engine. The only ford engine I'm aware of that isn't a duratec or zetec is the endura which is a very old engine.The only time I ever noticed a drop in power is after 25 minutes of hard driving a Silverstone.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 11:47:45 am
content: I think it is an Endura E, yes not the latest engine but to be honest it performs fine, had a car full yesterday and did 60 mph up a hill without loosing speed. But I know that it could do with being better on pull away and lower speeds hence the question.

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 12:07:22 pm
content: Rather than a turbo on the old Kent block you would be a lot better off taking the head off and having it gasflowed. Take the inlet manifold casting and get it cleaned up with a burr tool to get the sharp edges of the moulding away and you will have a lot better airflow where it counts. Pop it back on with a new gasket and new bolts and you will have a bit more power, if you want more lower down the cam will need profiling as well. I hope you are running a full synthetic oil as well, and changing the filter at 5000 miles ( they do tend to restrict flow at that mark mostly, though the service interval of 10000 miles is more for reducing the cost of motorplan payouts, as the engine will last longer even without servicing in many cases) to reduce the losses internally.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 03:03:17 pm
content: Well I don't particularly want to go as far as taking it apart, I'm not that handy on cars (adjusting tappets/valve clearances is my limit). The oil change interval on this engine is 5000 miles. I did the valve clearances on the last oil change, they were badly out, probably never been done, this greatly improved performance. I don't know if there are any lasting effects of valve clearances being far out ? it was so bad that going over 60mph was an effort and getting to 70 meant flooring it. Now i can do 70 with ease and dome 80 with no trouble.Does stuff like redX have any good effect ?

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 03:37:20 pm
content: Nope, better to buy a 250ml bottle of 2 stroke oil and pour in to the tank - has same effect and a lot cheaper. How black was the top end, that tells you how little the oil has been changed. Add a can of HD3 diesel oil to the sump and it will be sparkly clean after 1000km.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 03:40:28 pm
content: won't diesel oil do damage ? I think the oil was changed regularly as I got a well documented service book but I don't think they touched the tappets.What effect does putting oil in the petrol have ? might cause some interesting emissions

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 03:55:44 pm
content: Diesel oil contains more detergent, and will scrub the carbon and other deposits off the internal parts very well, and most will land in the oil filter and the oil. Do it and change oil and filter 1000km later, and go to a full synthetic as well. Will reduce drivetrain losses a few percent.The 2 stroke oil in the fuel is a 200:1 fuel/oil mix, will lubricate the fuel system and the injectors/ pump. Will be lightly toasted and will go out the exhaust where the cat converter will burn it and be a degree or ten hotter. Not going to harm sensors any more than the "Unleaded" fuel, which can have up to 0.2% of lead in any case. Remember the engine does get oil laden air in via the crankcase ventilation system as well ( have you checked the valves that are there that they are not coked up and blocked, very common on Ford engines) during running, it does no harm.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 04:09:40 pm
content: ah is that why there is a tube from the rocker cover to the air filter ? how do I check that valves are not blocked ?Where can I find all of the usual diagnostic values ? maybe comparing them with what I have on my reader will tell me if everything is fine.

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 04:33:44 pm
content: Funny thing is that there are no sensors to measure that............ Basically you check inside the pipes for crud ( buy a new one first as very likely they will break when you try to remove them, but they are cheap as OEM parts, do not try to use just any hose there as it will die a quick death) and check the small plastic parts for oil and carbon built up inside. Clean with carb cleaner inside, and rod out the small pipe inlets with a soft wire. When doing this clean under the oil filler cap as well, you will find it is dirty as well, as it is a cold spot.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 04:37:53 pm
content: not sure which bit your referring to ?

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 04:44:14 pm
content: The pipes are those from the rocker cover to the air cleaner, and there is a plastic valve assembly there under the filter ( or built into the air cleaner in some models) that gets the hot blow by gas to burn. When the valve blocks up the pressure builds up and can cause problems that do not show up other than poor running and fuel consumption. Blocked valve often stains the air filter in a spot with black oil.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 04:52:08 pm
content: There is no valve in the filter box, unless your referring to the bit of sponge that covers the hole where the pipe comes in. it is before the filter not after. The pipe on this engine does not come right out of the rocker cover but is attached to the filler cap and has some metal sponge stuff that was clogged in white mush, maybe I should give the cap a good clean or replace it ?

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 05:15:00 pm
content: Ah, the old Ford Sierra cap. You can buy it ( expensive) or clean it with carb cleaner ( blow through the pipes and the ends on the cap as well, and check them for cracking) and reinstall. The white is an oil and water emulsion, you must be doing little long distance driving if it is building up. More frequent oil changes are then recommended with this cycle. In the owners manual this is referred to as the arduous driving cycle. If you regularly drive more than 100km in one trip it will not appear.

author: Simon
author_rank: Unknown
timestamp: July 29, 2012, 05:23:46 pm
content: well I've ordered a new one. When I got it it had a rocker cover lid full of mush (yes water and oil). I cleaned it all out when I did the oil change and valve clearances.

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2012, 05:44:00 pm
content: So add the half litre of diesel oil, and do another oil and filter change in 1000km or a week. That will get a lot of the dirt out of the engine internals.

author: GK
author_rank: Super Contributor
timestamp: July 30, 2012, 12:41:25 am
content: Has this thing done a lot of miles? I'd keep diesel oil out of the crankcase if so, as that can quickly send a tired engine to its grave.I've seen a Landrover 2.25L die this way. The owner thought he was doing a good thing. The detergents in the diesel washed a crap load of carbon out of the engine, but there went the compression and the thing started burning more oil than petrol.

author: SeanB
author_rank: Super Contributor
timestamp: July 30, 2012, 05:08:44 am
content: In that case at least the rebuild was clean. Anyway those landy engines are generally poor compared to more modern versions ( I mean things designed after 1950, not just uprated and new kit bolted on) and in most cases they suffer from oil starvation on the back cylinders and then burnt pistons and valves.Best thing for Rover was being bought by BMW, at last they had an engine that did not leak oil in the first 5 years of service.

author: GK
author_rank: Super Contributor
timestamp: July 30, 2012, 05:33:09 am
content: The 2.25L was just an example of one demise I know of personally. I don't think the age of the engine design matters. The point was that the carbon build up on the rings and valve guides/stems in the mechanically worn engine was what was mantaining the compression and keeping the engine alive.How did we get from cold air induction to crankcase carbon anyhow?

author: Unknown
author_rank: Unknown
timestamp: July 30, 2012, 05:35:27 am
content: Quote from: GK on July 30, 2012, 05:33:09 amSomeone mentioned British cars.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 07:31:24 am
content: The car has done just over 50'000 miles. I don't think I need to put stuff into the oil as the changes seem to have been done reasonably regularly. I'll try the oil in the petrol and I'll be changing the filler/breather.

author: Unknown
author_rank: Unknown
timestamp: July 30, 2012, 07:52:19 am
content: Quote from: Simon on July 30, 2012, 07:31:24 amA good known brand oil conditioner or good brand oil flush is all that you need do. There are lots of product that claim to be "rings in a bottle" they don't work. Never have! Never will!The wrong grade of oil can be near as bad as no oil. If the engine is tired, which most 4 bangers will be by 100,000 Km (62,000 Miles) don't be temped with low viscosity rubbish, it'll just become expensive smoke. Is a mineral based oil one heavier than new spec and you should be right for a few miles yep. Expect to burn some though especially on wide open throttle.

author: itdontgo
author_rank: Regular Contributor
timestamp: July 30, 2012, 12:19:00 pm
content: Road cars work less effectively when hot mainly due to pre-ignition. The ignition is retarded when hot to minimise detonation which makes your internals hotter and the problem worse. You probably have a knock sensor on the block which can responds to the resonant frequency of the block during pinking.There I did it I used four words to describe the same phenomenon. Pre-ignition, detonation, knock and pinking ;o)Unless you're racing around a track who cares if your enigne is down a few horsepower? You shouldn't be using anything like max HP on the road anyway. Most cars only need about 10HP to do 50-60MPH.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 12:21:56 pm
content: well you see it's on pull away I notice a difference. And of course getting to 60mph. when you do short journeys a lot of it is acceleration to gain the top speed. If the engine performs less it needs take longer and more fuel to get to that speed at which point the consumption will drop.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 12:43:45 pm
content: Quote from: itdontgo on July 30, 2012, 12:19:00 pmwhich to me means very little so it is of no help. The discussion have naturally branched into many other engine aspects which I don't mind as I knew it would and this is not a motoring forum anyhow.

author: itdontgo
author_rank: Regular Contributor
timestamp: July 30, 2012, 02:33:27 pm
content: As an electronics engineer why not get an accelerometer and see if it's all in your head? What percentage difference in torque do you really think you can sense when it does not occur one run after another? Do you really think you can tell the difference between a hot and cold engine if you dont test one run exactly after another (which is of course impossible - your engine warms up slowly). You should also check for wind direction for fairness.I'm a weird car hating ex-professinal racing driver and I think cars should be restricted to perhaps 25-30BHP at the most. In which case I'd also say, this may be an interesting subject for discussion but is not really important to worry about how well your car accelerates.

author: T4P
author_rank: Super Contributor
timestamp: July 30, 2012, 02:47:17 pm
content: Quote from: itdontgo on July 30, 2012, 12:19:00 pm*1 hours later*Quote from: itdontgo on July 30, 2012, 02:33:27 pmWell, it sucks. Do that and you will suffer, like driving will be a nightmareBecause why? The more BHP you have the faster to hit 60mph, if you take longer you guzzle more fuel at best

author: itdontgo
author_rank: Regular Contributor
timestamp: July 30, 2012, 02:57:25 pm
content: I drive a 4.9L Cadillac Eldorado which could hit 60MPH pretty rapidly if someone other than a tight-wad like me was driving it. Are you saying we should all drive around in cars like this to save fuel because, let me tell you, you would be wrong!I may return to this topic when I've finished work!

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 03:19:38 pm
content: Well yes big engines are not the best. I had a 1.8L Monroe before and that drank. I'm not a car butter and not going to do all sorts of tests, it is more an idle interest. And yes I can tell the difference, I drive to the fuel consumption keeping an eye on my diagnostics panel. In fact I can do the test with it to check acceleration rates.

author: SeanB
author_rank: Super Contributor
timestamp: July 30, 2012, 04:12:55 pm
content: Well with the Uk price for petrol if you made a car that ran on milk it would be cheaper by far....... No wonder LNG conversions are so popular.

author: itdontgo
author_rank: Regular Contributor
timestamp: July 30, 2012, 05:59:52 pm
content: QuoteMotor car manufacturers make me sick using speed and performance to market their cars. As far as I am concerned they're worse than tobacco manufacturers as speeding modern cars are more likely to voilently kill someone innocent outside of the car. The occupants may be safe but the pedestrian, the cyclist, the kids playing in the street even the other motorists are put in more danger than the motorist who is speeding. And you know what, as much as I'd love to blame the motorist I dont because, if you legally give some half-wit a car that will go fast, you're telling the person it's OK. Just dont get caught eh!You think that it's OK? More people will die this century in road traffic accidents than in all the wars of the previous century which is ironic considering half of them were about oil. WW1, WW2, Hiroshima, Nagasaki, Korea, Vietnam... The auto industry is responsible for more death than the arms industry. 1.2million people per year to be exact. Market your cars on efficiency, luxury or engineering but not death!I expect you to disagree; motorists have got used to 100+BHP family cars saying, and I quote T4P, 'driving will be a nightmare [with 25-30HP]'. I think driving - along with living - would be far improved if dangerous high speed/acceleration driving was eradicated from everyday life. Cars are there to get places not for playing with. That's what race cars and tracks are for - a place where everyone involved knows the risks and accepts them. I stand by what I said 25BHP is plenty for the road no matter what size your car is. You just dont think it is because of the motoring culture we live in. If this was all new to you you would think it was insane to have high powered cars by where people live.BTW 30BHP is approx. 20kW. 60MPH ~ 27m/sTherefore energy:1/2 x m x v^2 = m x 364.5 JoulesIf your car weighs 600kg (a very small car) you could accelerate to 60MPH in <9s [(600 x 365)/20000]. This is like an 80s GTi. For a manufacturer to produce this car a lot of effort would be required in developing light cars with optmised engines and CVT transmission. It's a niche. If you want to drive an enormous car then you should go slow as your car is intrinsically more dangerous to everyone outsdie of it.

author: IanB
author_rank: Super Contributor
timestamp: July 30, 2012, 06:07:08 pm
content: I drove a car with a 29 hp engine (Citroen 2CV) for a time. It was a very light car, and was capable of 200 mile journeys in remarkable comfort considering it was a 1940's design. I'm sure modern designs could do much better.The downside is that headwinds kill you and passing slower drivers is difficult. And you are limited to a 65-70 mph cruising speed.But I do tend to agree that modern cars have vastly over sized engines for their function.

author: T4P
author_rank: Super Contributor
timestamp: July 30, 2012, 07:18:24 pm
content: Couple that with lots of extra safety electronics ... dick-electronics i call itand you see where i'm coming from, in the past my dad drove a proton GEN.2 (Don't laugh)and although it weighed 1.1tonnes and has 108bhp, it was just enough to break even.It's not about having 1100bhp 8L quad turbo engines, it's about having just enough balance to not be so fuel guzzling at 60mph and belowAlthough a M3 does better at fuel consumption than a Prius at 60mph but anything below that is pretty terrible

author: Zad
author_rank: Super Contributor
timestamp: July 30, 2012, 08:28:08 pm
content: The air temperature shouldn't matter, the engine should still use the same amount of air+fuel to accelerate to 60 in cold weather as in warm weather. Your foot is just applying a little more throttle but the power generated is still the same. The engine management has a lot of sensors to make sure the ideal mixture ratio is maintained over a wide range of conditions. The common exceptions being a cold engine and wide open throttle (WOT) where it goes open loop and enriches the mixture beyond the optimal, trading off emissions and efficiency for power.

author: IanB
author_rank: Super Contributor
timestamp: July 30, 2012, 08:35:42 pm
content: Quote from: Zad on July 30, 2012, 08:28:08 pmWide open throttle is the key thing. With a small, low power engine like a Ford 1.3 the accelerator is operated mostly in on/off mode. When you want to pull away smartly you put the pedal on the floor.Under these conditions of wide open throttle the power output of the engine depends on how much air it can breath. If the air density is lower the power must necessarily be reduced since there will be less oxygen available to burn the fuel.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 08:38:45 pm
content: Well as previously stated thinner air means less mixture and less power in each bang. Maybe I should look at the air intake sensor, the readings on the diagnostic panel are generally higher than ambient and no surprise will all the heat under the bonet. I think the radiator should have a shroud deflecting the air to the ground and not into the engine bay where the air can heat up in the extensive intake ducting which should also have reflective insulation around it.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 08:40:55 pm
content: Quote from: IanB on July 30, 2012, 08:35:42 pmThat is where my driving differs, is use 35% max and 50 on special occasions

author: WorldPowerLabs
author_rank: Regular Contributor
timestamp: July 30, 2012, 08:48:50 pm
content: Quote from: IanB on July 30, 2012, 06:07:08 pmOne of my vehicles is a late 1990s Ford van (V6, around 200 BHP). Believe me -- it is definitely not powerful, compared to the weight of the vehicle. I have to plan my merges onto the highway carefully, as I cannot accelerate quickly at all. I cannot pass other vehicles easily, either.My other vehicle is a late 1990s Lexus SC400 (V8, 260 HP). Again, it sounds powerful but it's a heavy car -- probably not as quick as a new Honda Civic. Still gets 20 MPG (measured).We also have a late 1990s Honda Civic. It's small, has a small engine, and is maneuverable -- but I hate working on that thing (and all other front-wheel-drive cars... engine is in sideways, can't even remove drive belts without tools).

author: IanB
author_rank: Super Contributor
timestamp: July 30, 2012, 08:57:09 pm
content: I don't know how you drive but many people don't do their highway merges appropriately. What you should do is plant your foot on the floor as soon as you enter the on ramp so that you are doing 60-70 mph by the time you reach the highway. You then synchronize with the traffic, brake slightly if needed to line up with a gap and then merge smartly in. Many people dodder slowly down the ramp at 30 mph, try to figure out what the traffic is doing, and then pull across while still going too slowly, causing the traffic behind to brake or switch lanes. It's an utter nightmare being stuck behind such a driver.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 09:00:57 pm
content: And my car just copes with sliproad merges.

author: WorldPowerLabs
author_rank: Regular Contributor
timestamp: July 30, 2012, 10:08:27 pm
content: Quote from: IanB on July 30, 2012, 08:57:09 pmYes -- you are absolutely correct, and I hate when folks stop in the entrance lanes, bumble along, etc. People should be at highway speed by the time they reach the end of the merge lane. Unfortunately, in NJ we have many merges that are so short that my van, even with the accelerator on the floor, cannot reach highway speed by the end of the merge so I necessarily must continue picking up speed on the highway. We also have those merges that are a combined entrance and exit -- those are a terrible invention. You'll have the folks who can't merge onto the highway, plus the ones who cut across 3 lanes in order to get in front of you as you exit!In my car, it's not a problem -- I can go from 40 to 70+ in the span of a normal entrance ramp.

author: Simon
author_rank: Unknown
timestamp: July 30, 2012, 10:11:09 pm
content: In the UK we have some horribly short entry lanes on "A" roads. They should be banned

author: Unknown
author_rank: Unknown
timestamp: July 30, 2012, 11:17:07 pm
content: Quote from: itdontgo on July 30, 2012, 02:33:27 pmAnd I'm Queen Elizabeth! mind the corgis! (Nurse! fetch me the net!)25hp is nowhere near adequate to propel one and a half tonnes of vehicle, goods and occupants over varying terrain at an acceptable velocity. Here is a quick quiz.You wish to merge into 100Kph freeway traffic from a 300m merging lane, how fast do you think your vehicle should be travelling at the point of merging?a) as fast as my under-powered traffic hazard can manage.b) 100 Kphc) 157 Kph

author: Unknown
author_rank: Unknown
timestamp: July 31, 2012, 12:05:31 am
content: Quote from: itdontgo on July 30, 2012, 05:59:52 pmCurious that it has been illegal to do so for some time to appease the nutjob minority! But hell why let that interfere with a good rant!QuoteCars do not kill any more than guns do or chain saws do when operated correctly. Guns have little practical use in modern society, motorised transport is essential. We are not going to ban things every time some nutjob has a rant.QuoteStatistically vehicle occupants are those most likely to injured by misuse or ignorance in operation.QuoteYou know what? We don't give a flying f**k what flawed conclusion you may have derived from your misinterpretation of data?QuoteMore people died in travel related incidents prior to the modern automobile, you do not have to read too many 19th century tombstones to realise travel has always been a dangerous pursuit. What's your alternative? Shut down the roads and all industry and have the population perish due to consumption and dysentery?QuoteShort of suffering an extensive head injury in the course of the day, I'd say the chances of my subscribing to your crackpot nonsense is exactly zero.QuoteI think the world would be a better places if clueless nutjobs who see it as there place to dictate how others live, were dispatched on the "B" ships as soon as possible.QuoteThat's why they all pile up on the first corner right?QuoteYeah your a believer in bollocks. Hundreds of rural Americans believe UFOs always arrive on bourbon night. Why should the rest of us have to listen to your manic ravings?QuoteAssuming there is no relationship between size or mass. Unfortunately for the accuracy of your ravings, there is.QuoteWhat measure says a couple of hundred well regulated HP is insane? The rantings of you, a practising nutjob?QuoteIt is eithera) a modern pramb) fictitiousc) manufactured entirely of unobtainium (see b)d) wholly inadequate for transporting goods, a family, or even your great aunt who need to see a chiropodistQuoteBut safe road cars do not weigh 600 kgs so you are talking bollocks.QuoteEvery time them manufacturers shave Kg of vehicle mass you and the rest of the teapot brigade lobby up hard for another piece of save us from thyselves crap, which is mostly why modern cars are so obese. Why cart round Kg of airbags to cater for those too stupid to wear a seatbelt. It's only delaying Darwin from having his way.QuoteSo it's size that is dangerous then? A minute ago it was speed? So my larger car that will out-brake out-handle out-steer, out-perform any POS noddy hatchback is actually the danger? How is that? Will it cause you and the rest of the anoraks to die of envy?All I can suggest is that you and any other teapot that see sees it as his business to dictate to others, should forthwith go learn the ancient and essential art of "shut the f**k up"! No that would make the world a better place.

author: Stephen Hill
author_rank: Regular Contributor
timestamp: July 31, 2012, 08:56:05 am
content: Simon, a question that hasn't been asked is, what is your budget for improving the power of your engine?I'm going to first recommend you buy and install a good air filter system such as the BMC CDA Air Filter (Similar systems are available from other manufacturers).When installing, you want to make sure that you make the shortest path from the front of the car to the throttle body. The housing of the air filter is designed to reduce the heat up of the intake air.

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 09:04:44 am
content: Hm don't want to spend more than £100, 200 for something that really makes a definite difference.

author: Stephen Hill
author_rank: Regular Contributor
timestamp: July 31, 2012, 09:50:49 am
content: Quote from: Simon on July 31, 2012, 09:04:44 amWell then I'm not sure you're going to make any real difference because unfortunately, improving performance costs money. You can only hope to regain some performance through good maintenance.You could of course make your own direct air intake system using a relatively cheap aftermarket cone air filter and some ducting. It won't look as good as an off-the-shelf product, but it will do the same job.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 31, 2012, 10:40:07 am
content: What Stephen said ^Get down to halfords and get an enclosed filter and B&Q for some ducting

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 12:47:04 pm
content: as many have said the stock filter is not that bad, I took a look and yes it has quite a lot of surface area. Looking at my dads fiesta with a 1.25L zetec engine (same model car 1 year younger) his filter box is much larger and right on top the engine/injector.The other thought I have is that if you have enough volume of tubing (or other housing) between the air filter and injector you have a reserve of air the engine can draw on (like a bulk capacitor). or is that the wrong logic ?

author: IanB
author_rank: Super Contributor
timestamp: July 31, 2012, 12:53:47 pm
content: Quote from: Simon on July 31, 2012, 12:47:04 pmUnfortunately, yes. It is all about air flow. There is no functional air reservoir in a vehicle intake system.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 31, 2012, 12:57:59 pm
content: I remember seeing the calcs before and to have a useful reservoir of air you're looking at needing around 40 litres

author: Stephen Hill
author_rank: Regular Contributor
timestamp: July 31, 2012, 12:58:48 pm
content: Quote from: Simon on July 31, 2012, 12:47:04 pmThe stock system air intake system isn't designed for performance, it is designed for quietness and fuel economy. This is why people like to add aftermarket air filters to their cars because it makes a sportier note in the low to mid rev range.I'm not sure if the extra area inside the tubing will have that effect but it's an interesting question.I've just used this online air intake calculator and at idle, your engine would be breathing in 10 litres of air every second so no amount of tubing would have any effect. But this does highlight having a short unimpeded route from the front of the car to the throttle body.At 6,000 RPM, your engine would be breathing in about 60litres/second.

author: Unknown
author_rank: Unknown
timestamp: July 31, 2012, 01:08:17 pm
content: Quote from: IanB on July 31, 2012, 12:53:47 pmThat's it! and What is drawn/forced in has to get out again. Everything from inlet to exhaust has to be capable of of desired flow. Jumbo intake and exhaust aren't going to help much if flow has to be squeezed through asthmatic heads an budget manifolds. In fact going too far can actually reduce HP.

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 01:27:49 pm
content: I have quite a length of pipe from my air filter in the front right corner to the back of the engine. the higher performance zetec seems to have the filter body attached to the injector. I'm thinking that if i get say a mondeo filter box and filter it would be at least twice the size and let the engine breath more easily, or get any other faster flow rate filter.

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 01:55:12 pm
content: Quote from: Uncle Vernon on July 31, 2012, 01:08:17 pmThe exhaust is forced out under pressure (so much it can drive a turbo), the problem is letting air in easily at the moment.

author: Unknown
author_rank: Unknown
timestamp: July 31, 2012, 01:57:47 pm
content: Quote from: Simon on July 31, 2012, 01:55:12 pmWhatever you reckon. Don't say you were not told.

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 02:10:58 pm
content: Is this filter:http://www.knfilters.co.uk/search/product.aspx?Prod=33-2804going to be any good (well not do damage) ? I'll also be inclined to get some stuff to wrap round the ducting and help stop the air heating up in the duct.

author: SeanB
author_rank: Super Contributor
timestamp: July 31, 2012, 03:50:59 pm
content: Well, you do not drive on dirt roads, so it will do better than no filter, and will keep sand out. You will be surprised just how little drop there is across the standard unit, if you want get a vacuum gauge and see what the drop is, though you probably will need a differential gauge that reads mmH2O to get a good reading ( ie pretty low drop). Biggest loss in your engine is the inlet manifold casting, and the inlet section of the head. Nothing short of a machine shop will change that.Go look at Cosworth to see what they can get out of that engine.

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 08:17:46 pm
content: the other thing of course is that the intake air sensor is probably in the injector body and that will get warmed up by the engine block it's attached to ? I had readings of 47C today, it dropped to 44 thought when I popped round the corner and stopped so I think part of it is the heat in the engine bay and coming out of the radiator.

author: G7PSK
author_rank: Super Contributor
timestamp: July 31, 2012, 08:29:52 pm
content: Most car intake systems are tuned length so as to make the air flow as smoothly as possible while at the same time being as quite as possible, they act as ram chargers. If you start messing with the induction system you can and will most likely make things worse as the valve timing will also need to be altered in order to keep the best possible scavenging of the engine.It's the weight of the air in the induction system that helps with the scavenging, that's why with a turbo or supercharge you can have far more valve overlap, it is just not as simple as sticking a bigger filter on the engine you may also find that with a modern management system the car will not run properly or not meet the emission regulations. The engine manufacturers do not spend multi millions on test rigs in order to best optimize the engine for nothing and it is highly unlikely that any go faster gizmo sold for a few quid will work any better than painting stripes on the side of the car.

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 08:32:31 pm
content: Oh I'm not going to touch the intake system, just commenting on how sensor readings come about.

author: Unknown
author_rank: Unknown
timestamp: July 31, 2012, 09:16:54 pm
content: Simon, is there anything to be gained by making a radiator out of copper instead of aluminium as they normally do?For example do I want a copper radiator or intercooler in my F1 car?

author: Simon
author_rank: Unknown
timestamp: July 31, 2012, 09:24:04 pm
content: Quote from: HAL-42b on July 31, 2012, 09:16:54 pmIt will cost you much more and may or may not be as rugged. Our copper/brass radiators usually don't go up to more than 1.5 Bar (21 psi) and don't like over pressure. Aluminium plate and bar is very rugged and even an inter-cooler will take peaks of 5Bar where as a copper tube radiator will go bang long before. Then again we make air con condensers for air con systems that take 20+ bar. It's a fine art. copper will loose heat faster but will weigh more and has different construction techniques. You have to solder or silver solder copper which is expensive (silver solder is £400/Kg !!!) aluminium can be braised in an oven or welded which is cheaper.Are you just asking a question or trying to make a point in the current debate ?

author: Unknown
author_rank: Unknown
timestamp: July 31, 2012, 09:31:49 pm
content: Quote from: Simon on July 31, 2012, 09:24:04 pmJust asking, couldn't figure it out.

author: Zad
author_rank: Super Contributor
timestamp: August 01, 2012, 04:28:06 am
content: A K&N or similar air filter will increase induction noise slightly, and give the impression that the engine is more powerful. It may be slightly more powerful, but only measurable under hard acceleration. Depending on your driving style, you may see more benefit from uprating the anti roll bar bushes to Polybush or similar. Standard ones do degrade over time and make te handling rather wallowy.Ford's Zetec engines are very modifiable and have a huge motorsport user base, but to do it properly requires engine management re-mapping, new exhaust, freeflow catalyst, cams etc. With modern road cars, there is only really one reliable way of getting more power without all sorts of knock-on driveability issues and insurance problems. That is to sell it and get one with a bigger engine. The Mondeo V6s are great engine and show what a good chassis the car has. Unfortunately, you'll struggle to see 30mpg.As an aside, don't mistake resonator chambers for storage chambers. They exist to tune out nasty resonances that can appear in induction systems and cause nasty problems.

author: Simon
author_rank: Unknown
timestamp: August 01, 2012, 07:12:56 am
content: Except I have the endura engine

author: Chet T16
author_rank: Frequent Contributor
timestamp: August 01, 2012, 09:45:26 am
content: I think you should just take your back seats out

author: G7PSK
author_rank: Super Contributor
timestamp: August 01, 2012, 12:39:46 pm
content: Or empty the boot of all that junk.

author: Simon
author_rank: Unknown
timestamp: August 01, 2012, 01:48:14 pm
content: Quote from: G7PSK on August 01, 2012, 12:39:46 pmI have none, I keep as light as I can

author: Zad
author_rank: Super Contributor
timestamp: August 02, 2012, 05:03:42 pm
content: Quote from: Simon on August 01, 2012, 07:12:56 amAaah, I got accidentally misled when you mentioned the higher performance Zetec. The Endura-E engine is basically an updated Ford Kent lump which started life in 1959 in the Anglia. 8 valve, iron block and not massively good for modding sadlyDefinitely not drive-by-wire, and I think only single point fuel injection with single cat sensor.It was popular in the 70s and 80s in it's Crossflow incarnation, but time moved on. Good reliable things, but save your money and part-ex it for a Zetec or Yamaha 1.25 (check the Nikasil liners on those). Much more modern engines with better control systems, more power and better efficiency.Edited to add: Try slightly over-inflating the tyres to just above the manufacturer's spec. Obviously keep it below the "heavy loaded" rating in the handbook.

author: Simon
author_rank: Unknown
timestamp: August 02, 2012, 05:28:32 pm
content: Well the mileage is not too bad. I think consumption has improved after putting 1/2 litre of 2 stroke oil in the tank (40 litres). I've just fitted a new filler as the original one was full of mush in the gauze so probably restricting breathing and letting air get out to the intake and I guess a sensor (It has two tubes coming out). If you think zetec is so efficient get my dad to drive it then you'll see. He swears by the endura engine (he had an escort with the previous incarnation) and reckons he gets poor mileage out of both the last escort with a zetec and now his fiesta with a zetec. Problem is he never puts his foot down and keeps the engine in "working hard to try and build up speed mode" On my engine i found I'll get the same millage at 70mph as I get at 50-60, the trick is getting to 70 and staying there

author: Zad
author_rank: Super Contributor
timestamp: August 03, 2012, 05:19:48 am
content: Yep, twin-cam engines tend to work better at higher revs, as they inherently breathe better at higher airflow rates. At low revs the reduced turbulence isn't as good as an 8V engine at mixing the air/fuel. I have noticed older drivers tend to change up early and labour the engine rather than change down, in the belief that it is more economical.My dad used to drive a Sierra 2.0i GLS with the old Pinto engine. He upgraded to a V6 Mondeo with 50% more power, power-sapping aircon, heavy (motorised) leather seats, crash protection etc. And still gets 6-8mpg more than the Sierra. That's technology for you.I wouldn't make a habit of putting oil in the fuel tank, that's a pretty good way to kill the catalyst and carbon up the combustion chambers. From your description, the sensor with 2 tubes might have been the crank case ventilation pipe with filter that stops oil drops being spat out.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 03, 2012, 06:02:09 am
content: Quote from: Zad on August 03, 2012, 05:19:48 am*I don't,& I am definitely an "older driver".When I learnt to drive,we were told "You must be in the correct gear at all times!"This entailed changing up,& just as importantly,down,at the correct times,so that, for instance,when approaching a red traffic light,you would change down through the gears,finally ending up in first when stationary at the lights.If the light goes green when you are in,say second gear,you can smoothly accelerate through the intersection,& change up again.The way they teach nowadays in Western Australia leads to people slowing down to a stop in top gear,then hurriedly trying to get into first gear so as to be ready to take off.If the light changes,they are not in the correct gear to smoothly continue.This behaviour is very similar to the normal way of driving an automatic,so maybe the motivation is: "They'll all be driving automatics anyway,so why confuse them!"

author: Simon
author_rank: Unknown
timestamp: August 03, 2012, 06:15:31 am
content: Quote from: Zad on August 03, 2012, 05:19:48 amAnd how heavy was that sierra ? The mondeo's are actually quite light which will give you a mileage gain no matter what the engine is. The mondeo I just got rid of was 1.8L and weighed just 1470 Kg which is amazing when you consider my fiesta is 1400 ! The mondeo was infact considered a high performance car for insurance purposes for the sheer power to weight ratio and cost me a fortune to insure.Yes my dad alsways try's to make the engine run at too low revs, you can feel the engine labour. He has decided it should drive just like his cars with a pinto engine. The difference is that while my engine does 3200 rpm at 70 mph his probably does 2500 and is much quiter at high speeds and nicer for long distances. That said having done the valve clearances it got quieter at high speeds and chattered a it more at lower. My engine though has no cambelt

author: Zad
author_rank: Super Contributor
timestamp: August 03, 2012, 08:33:09 pm
content: Quote from: Simon on August 03, 2012, 06:15:31 amI can't tell you how heavy my dad's car was, but my XR4x4 with an iron block engine and 4x4 transmission and steel wheels is 1250kg, so it would be significantly lighter than that. The V6 Mondeo with toys is 1510. Amazing how technology moves on!Only early Zetecs are belt drive, the rest are chain drive.

author: Simon
author_rank: Unknown
timestamp: August 03, 2012, 08:38:30 pm
content: well did 200 miles today, 50 miles into the journey it was like the engine sudenly unleashed, it was nippier and fuel consumption dropped considerably from about 5.5 L/100 Km to 4.5L/100km. No idea what happened but very pleased and itall runs smoother like just pulling the car in first with no acceleration.Pity on the way back we started to boil over so something wrong with the wiring to the fan. Had to come back with the hot air on.

author: SeanB
author_rank: Super Contributor
timestamp: August 04, 2012, 05:59:20 am
content: Thermoswitch is faulty ( very common, and the generic one is very cheap, about 4GBP here) or the fan brushes or bearing are dead.The boost in power was the catalytic converter finally getting hot enough to do a self clean cycle and burn off all the carbon inside, which made it flow a lot freer than before. Must have had a lot of short trips and nothing long with previous owner. the gunk in the oil filler is evidence of this, you will find nothing in there now.

author: Simon
author_rank: Unknown
timestamp: August 04, 2012, 06:18:16 am
content: Quote from: SeanB on August 04, 2012, 05:59:20 amThis all works off the ECU, my diagnostics reader is getting temp information so the sensor works but at 98C there is no power in the fan plug.

author: SeanB
author_rank: Super Contributor
timestamp: August 04, 2012, 02:05:07 pm
content: Sensor reading is to control idle and cold enrichment values. When cold it runs rich, and it will lean out and change from open loop EGR and mixture control to lambda control when the engine is hot enough, and has driven enough to warm up the exhaust. Then it will refine injection timing and timing to run at a lean mixture without knocking being detected by the knock sensor.

author: Zad
author_rank: Super Contributor
timestamp: August 05, 2012, 02:32:23 am
content: Quote from: Simon on August 03, 2012, 08:38:30 pmThat's otherwise known as an Italian Tune-Up! All cars benefit from them now and then.The catalyst burning off carbon has been explained, but another side effect of getting your engine nice and hot (within normal limits) is that it burns off water condensation in the oil, which can normally cause wear problems and reduce efficiency.

author: Unknown
author_rank: Unknown
timestamp: August 05, 2012, 07:45:21 am
content: Quote from: GK on August 05, 2012, 07:30:31 amWould be magic but then there is the flow through those heads.

author: Unknown
author_rank: Unknown
timestamp: August 05, 2012, 11:44:17 pm
content: Quote from: GK on August 05, 2012, 11:06:39 amTragic!And just when it was starting to deliver some worthwhile results.

author: GK
author_rank: Super Contributor
timestamp: August 06, 2012, 12:16:43 am
content: Pffft!!!!!!Makes more power than that crappy Ford engine would with the blower unbolted and n/a LPG induction bolted on top instead!

author: Chet T16
author_rank: Frequent Contributor
timestamp: August 06, 2012, 12:57:41 am
content: Hey guys, you know they make cars that go around corners well now? :p

author: Unknown
author_rank: Unknown
timestamp: August 06, 2012, 01:05:05 am
content: Quote from: GK on August 06, 2012, 12:16:43 amWhy would I remove the blower and run on BBQ fuel? To remove an unfair advantage?Still could be worse, you could have been stuck with something from Europe!

author: Unknown
author_rank: Unknown
timestamp: August 06, 2012, 01:14:15 am
content: Quote from: Chet T16 on August 06, 2012, 12:57:41 amThose ass dragging turbo teapots your talking about will go round corners with no regard to where you were actually intending to go!

author: GK
author_rank: Super Contributor
timestamp: August 06, 2012, 01:21:00 am
content: Quote from: Uncle Vernon on August 06, 2012, 01:05:05 amWas just adding some perspective.Anyway, when I go on a picnic down at the local drag strip I can fry my tofu burgers on the grill in the boot.

author: Unknown
author_rank: Unknown
timestamp: August 06, 2012, 01:33:26 am
content: Quote from: GK on August 06, 2012, 01:21:00 amAt WSID they only serve TOFU and Fairy Bread on 4's and Rotary nights!

author: GK
author_rank: Super Contributor
timestamp: August 06, 2012, 04:23:09 am
content: Tofu is Iron Man food.

author: charliex
author_rank: Frequent Contributor
timestamp: August 06, 2012, 06:26:21 pm
content: I was just reading through the couple of ecu/air threads, and late to the game, but i thought i'd throw a few opinions into the mixThe air intake of an engine at its smallest point isn't in the air intake, the restriction is at the inlet.A NA engine takes air in til it equalises the atmospheric pressure in the cylinder.The inside of an engine (and the bits leading into it) is very going to extremely hot, any colder air is going to raise in temp very quickly, air will expand very quickly so density will drop very fast, very little will overcome the temperature in the cylinder. There's nothing forcing the air in, just the same equalisation and how much air the inlets can flow. More dense air can get more air into the cylinder quickly, but how long do you think colder air will stay cold in an combustion chamber? (about 800-1700C), Cooler is better though, but it could be a fraction of a percent.Most CAI claims are potential horsepower, that you can potentially run a more aggressive advance to take advantage of denser air, however ECU's are tuned to run at the correct AFR for whatever was wanted at the time of the tune. However a more aggressive advance doesn't always equate to more power. On a closed loop car the ecu will alter the fuel mix if the air density changes since that will change the mix, the O2 sensors will pick it up and it'll adapt the fuel being fed. In open loop mode its usually fixing the fuel rate, but there is no guarantee that is greater horsepower, too lean you'll lose power and the temps will increase substantially, increased temperature can makes pre-det/det more likely, and then cylinder pressures can be catastrophic, some engines can take a det all day long, some will explode immediately.Pre-det and det can be reduced with denser/colder air, but you if you're getting pre-det its probably really hot ambient anyway, or a fault/fueling issue, and the ecu will see it and account for it, usually by immediately dropping the advance and adding fuel by swithing to a 'hot' or safe map, If you're getting det somethings probably seriously wrong anyway.Car OEM's designers don't underspec air intakes. Tech can change that could potentially improve it, but saying that, car models come out ever year.CAI's usually make more noise, that's about the only solid proof on the generalised answer.Lots of aftermarket CAI's are poorly designed, and often loose features that destroy the laminar airflow that is required for the MAF sensor to read correctly, turbulent airflow is bad, it can result in poor idle, and poor running.Resetting the ecu by leaving it off for a while is rarely true anymore, as is reflashing the chip to make sure its ok, the closed loop parameters are usually stored in some sort of non volatile ram/eeprom and the firmware has checksums that if its got a fault it won't boot, or start.cheers,charlie

author: IanB
author_rank: Super Contributor
timestamp: August 06, 2012, 07:15:24 pm
content: Interesting comments, but a couple of thoughts in response:Firstly the air heating up on entry to the cylinder. I rather doubt the cylinder walls are as hot as 800 C as they would be glowing red hot at that temperature. Given the water cooling in the block I would imagine something more in the 150-200 C range. Considering then the heat transfer to the air, there is only a fraction of a second before the inlet valve closes during the intake portion. I'm not sure how likely it is that the air can equalize in temperature with the cylinder walls in such a short time. There will be a little heating to be sure, but maybe not all that much.Secondly, laminar flow in the air intake also sounds unlikely. Rapid airflow in a large duct is going to be turbulent under all typical circumstances. I could do a quick calculation to check at some point, but it goes against all my engineering intuition to imagine laminar flow there.

author: Simon
author_rank: Unknown
timestamp: August 06, 2012, 07:30:10 pm
content: well that corrugation in my ducting for flexibility won't make it a smooth passage. Who cares how the air gets in, so long as it gets in.

author: charliex
author_rank: Frequent Contributor
timestamp: August 06, 2012, 07:33:46 pm
content: Hi IanB,Yes at the inlet , 200C would be a good guestimate, but we're talking marginal differences in air temps.On a lot of OEM intakes, there is a small plastic vane (or such) just before the MAF sensor that helps to get a laminar flow, aftermarket CAI's usually don't have them, which is why you'll often see complaints of a rough idle after a CAI installation. Often everything is removed by the aftermarket to make it look like its less restrictive, or simple a mass manufacturing cost.As well as that people will often install them incorrectly (or bad design) so they've got a bend just before the sensor and the MAF won't correctly meter the air.Incorrect metering of the air at the MAF sensor = bad fuel calcs = poor performance, mileage. thats why you care.cheers,charlie

author: Simon
author_rank: Unknown
timestamp: August 21, 2012, 06:49:39 am
content: well I have some information for those who tell me how much effort goes into getting that 1 filter speced that matches the engine. My sister has kust bought a KA, year younger than mine, same engine. The air filter has been moved, while this looks like a space saving measure (because the section of engine bay where my filter is on my fiesta does not exist on the ka) it is in an existing gap that is also in my fiesta but left unused, much closer to the engine, the intake duct is now inches long not feet and the filter, the filter is 50% bigger !!! for the same engine on a lighter car (that really pulls away quick !). I'm wondering if it's worth getting a stock KA filter and box and fitting them in the available gap. The engine bay layout is all the same, it is just that on the fiesta they choose to put the filter further away with more ducting.

author: G7PSK
author_rank: Super Contributor
timestamp: August 21, 2012, 07:18:16 am
content: A well designed NA engine will actually get slightly higher than atmospheric pressure in the cylinder due to the momentum in the column of air entering the engine compressing the air already in the cylinder before the inlet valve closes.

author: Simon
author_rank: Unknown
timestamp: August 21, 2012, 11:55:59 am
content: really ? air is not exactly heavy. Are you saying that the 2 foot duct from the filter to the injector is acting as a compression chamber ?

author: Bloch
author_rank: Unknown
timestamp: August 21, 2012, 12:40:13 pm
content: *SimonMy small GM motor have a "TwinPort" intake port.http://en.wikipedia.org/wiki/TwinPortHere is mentioned it is possible to tune a intake port to act like a supercharger over a narrow engine speed band.http://en.wikipedia.org/wiki/Helmholtz_resonance

author: G7PSK
author_rank: Super Contributor
timestamp: August 21, 2012, 04:23:10 pm
content: It is down to Newtons laws of motion, the first.

author: Simon
author_rank: Unknown
timestamp: August 21, 2012, 07:19:24 pm
content: Quote from: Bloch on August 21, 2012, 12:40:13 pmInteresting, and contrary to what others suggested: swirly airflow is good. Well the duck size is the same on the fiesta as on the ka but about 8 times longer and smaller filter area. From that link is suggests this is good for low load/low speeds, shorter tracts are better for high speeds. Now I'm not sure what is classed as low or high speed but my gut instinct is that when they got to do the ka they took a decision to redesig the filter and duct

author: EEMarc
author_rank: Regular Contributor
timestamp: August 21, 2012, 08:23:07 pm
content: Quote from: Simon on August 21, 2012, 11:55:59 amFluid mechanics can be used to tune an engine. If the intake manifold is a long smooth tube, then you can increase the pressure. Keep in mind that this effect is small. What happens is during the intake stroke, air moves through the tube building momentum. Nearing the end of the intake stroke, the momentum continues to push air in. Ideally when the air stops blowing into the intake valve(s), the cam will close the valve and maximum pressure will be achieved. Usually the cam can only do this for one RPM unless it is a variable cam. Usually it will be tuned somewhere in the middle of the power band to make the most use out of it during hard acceleration. At higher or lower RPMs, the air will either not fully stop leaving cutting out some of the air or reversed air flow will cause some of the air in the cylinder to blow out.The end result is volumetric efficiency. As Uncle Vernon pointed out in post #60, the VE ranges from 85- 105% depending on the engine. Anything below 100% on the scale means that the intake is actually restricting airflow. Anything over 100% means that there is some natural aspirated boosting going on albeit not very much. Stock engines are typically on the lower end of that range, but some are higher up if care was taken with regard to the air intake. Optimally, you could get higher than that, but there are diminishing returns on investment.Fluid mechanics are also used to lower the cylinder pressure at the end of the exhaust stroke with carefully made exhaust headers. This helps remove some of the remaining exhaust from the cylinder at the end of the exhaust stroke limiting how much exhaust contaminates the next intake stroke.Turbulent air flow will inhibit the resonance effect. Ideally, the airflow doesn't become turbulent until after entering the combustion chamber where it can homogenize the fuel mixture without reducing the VE of the engine.

author: Zad
author_rank: Super Contributor
timestamp: August 22, 2012, 12:17:27 am
content: To reinforce these comments, it is possible to get very high volumetric efficiency indeed if you don't mind running the engine over a very narrow rev range. 2-stroke racing motorbikes in the 1960s were able to get over 200bhp/litre by using resonant induction and exhaust systems. I imagine they were a bugger to use though. In modern engines, it is common to have the inlet and exhaust valve timing overlap slightly. This is because the inertia of the exhaust gases is still evacuating the chamber although the piston has started the induction stroke. The partial vacuum helps draw the new mixture in, increasing volumetric efficiency. The downside is that this causes problems at lower engine speeds, hence engines with variable valve timing.When you start modifying the car to this extent, you risk knock-on problems with the rest of the system, and insurers may start charging you a premium for having a modified car. If you do change the induction system, consider swapping the catalyst for a straight-through or gutted pipe too. There is no legal requirement here in the UK for cars to have a catalyst on the road, only that the emissions when tested must comply. My 1991 Sierra (which never had a cat) passed it's last MOT with emissions that would have been a good pass even for a cat car.

author: Unknown
author_rank: Unknown
timestamp: August 22, 2012, 12:43:20 am
content: Quote from: Zad on August 22, 2012, 12:17:27 amGot it in one! Changing any aspect while ignoring others is likely to return any dividend, and can often result in net detriment.QuoteWhy it is plain dumb to try applying track stuff to road usage.Quotetoo true. So will however stillbe astounded that one of the first measures taken when chasing big numbers out of taxi pack engines is to fix that valve timing.QuoteIt's all about interactions and compromise. You can turn a Nana car into a fire breathing monster, but you cant do it economically, nor will it remain something she will wish to drive to the post office.QuoteBasically it's a dickhead tax! Those who attempt the impossible mechanically often drive with similar traits.QuoteWhile the straight through thing was traditionally the way to go, most engines built this century will run worse unless appropriate back pressure is maintained. That illegally modified cat converter is often robbing horsepower.QuoteGood luck cheaply meeting those requirements without a cat on most vehicles.QuoteYes it was engineered that way, the congested povvo pack variants wont have such a easy time being able to comply. The regs however are something of a joke as they do not take into account varied usage of vehicles. Compliance at idle does not necessarily equate to engine efficiency.

author: NiHaoMike
author_rank: Super Contributor
timestamp: August 22, 2012, 02:10:21 am
content: Quote from: Uncle Vernon on July 26, 2012, 11:57:53 pmhttp://en.wikipedia.org/wiki/Hybrid_turbochargerIt's an idea that would theoretically work. Problem is, by the time you have all the parts, you might as well just drive the wheels directly like all production hybrids do. The turbine in the exhaust to recover energy is a good idea until you realize that Atkinson cycle (increasing the expansion ratio relative to the effective compression ratio, generally done by modifying the intake cams) gives you the same effect with just a slight redesign and retooling cost. The compressor in the intake is also a good idea for varying the effective compression ratio to get peak efficiency, but variable valve timing does that for cheaper.Really, Toyota set a high bar with the Prius. Other auto makers have tried to beat it and failed (excluding limited range all electrics and expensive PHEVs). One of them - Hyundai - had a potential winner with their already very efficient Sonata with direct injection and high energy ignition, then they added their innovative hybrid system with a Lithium battery and modified DCT that would theoretically give better efficiency than the Prius, but fell short in the real world.And a small but high volume compressor does indeed exist, but only at well below 1 ATM, useless for use in engines. My friend Brittany Benzaia built a hybrid A/C that has one of those inside.

author: Simon
author_rank: Unknown
timestamp: August 22, 2012, 06:08:07 am
content: Quote from: Zad on August 22, 2012, 12:17:27 amah yes they also changed the valve clearances. Originally both were 0.5mm now one is 0.2 and the other 0.3, engines that came later with the new specs had a label put on the rocker cover with the new settings. some people on the fiesta forums go down to 0.1mm, not sure I want to risk smashing my engine thought.

author: GK
author_rank: Super Contributor
timestamp: August 22, 2012, 07:56:13 am
content: Quote from: Uncle Vernon on August 22, 2012, 12:43:20 amCompletely untrue for any turbo charged engine and mostly a myth for normally aspirated engines also.

author: GK
author_rank: Super Contributor
timestamp: August 22, 2012, 08:32:17 am
content: Here you go - myth #5:http://autospeed.com.au/cms/title_Automotive-Myths/A_111396/article.htmlIn my own dabblings with various modified engines of my own I have yet to speak to a highly experienced tuner or performance engine builder who hasn't conveyed the same opinion.

author: Simon
author_rank: Unknown
timestamp: August 22, 2012, 08:45:37 am
content: The other thing I noticed is that the ka came with "4 point" spark plugs. Are these really any good ? or just a fad ?

author: EEMarc
author_rank: Regular Contributor
timestamp: August 22, 2012, 10:10:53 am
content: Quote from: Uncle Vernon on August 22, 2012, 12:43:20 amCar manufacturers are generally focused on emissions before efficiency. Once the STFT approaches the stoichiometric fuel mixture as read oxygen sensor, it will then oscillate from rich to lean back and forth. This hurts the efficiency but allows the cat to improve the emissions.

author: EEMarc
author_rank: Regular Contributor
timestamp: August 22, 2012, 10:23:26 am
content: Quote from: GK on August 22, 2012, 07:56:13 amPutting a turbine on the exhaust puts a substantial amount of back pressure on the engine, particularly at WOT and lower turbine RPMs. I don't think a turbo really counts.On the other hand, an engine often needs to be tuned if any big fundamental changes are made to it. A step often missed by many car modifiers to my entertainment.

author: Unknown
author_rank: Unknown
timestamp: August 22, 2012, 01:04:33 pm
content: Quote from: GK on August 22, 2012, 08:32:17 amYes it backs up what I have said ........."But that decrease is nearly always because the engine isno longer appropriately tuned! For example, after being fitted with a big exhaust, MAP-sensed engine management systems may run leaner than optimal. Ignition timing is also likely to beno longer best for performance."...... Removing a Cat in isolation is only going to sap HP.QuoteI was talking about stuff built this century. Is the BBQ bus going to meet that criteria?QuoteDepends on which ones you talk to. Time-slips andcorrectly operateddynos, do not lie. A lot of monkey with red overalls will tell you whatever you want to hear, right up until your wallet is empty.

author: Unknown
author_rank: Unknown
timestamp: August 22, 2012, 01:07:08 pm
content: Quote from: EEMarc on August 22, 2012, 10:23:26 amEven for moderate changes......QuoteThe gentle art of watching turd polishers.

author: SeanB
author_rank: Super Contributor
timestamp: August 22, 2012, 03:42:58 pm
content: The 4 point plugs help if you are running a very lean mix, as it has an increased chance of igniting the mixture. What helps more is higher ignition power, though most modern systems have CDI, or times charging via an ECU, so they do have a more powerful spark which will ignite very lean mixtures. In the 1980's my father had an Alfa ( roll on the jokes about built in rust) which he upgraded with a high energy coil. Normal plugs in this would last under 1000km before they lost the ground electrode, the then new Bosch platinum lasted even less, the only ones that would do the 10000km between services were a 4 point Lodge one, and even those had significant electrode erosion when removed, often being around 5mm eroded up into the body.

author: Simon
author_rank: Unknown
timestamp: August 22, 2012, 04:39:50 pm
content: so it's just as good a bang as a single point one. I guess the idea is that 4 sparks have more chance of catching some fuel in a lean mix than one

author: SeanB
author_rank: Super Contributor
timestamp: August 22, 2012, 05:29:37 pm
content: You do not get 4 sparks, just you get 4 chances per cycle of the spark being in a region of rich mix, so making it fire.

author: Simon
author_rank: Unknown
timestamp: August 22, 2012, 05:35:47 pm
content: Quote from: SeanB on August 22, 2012, 05:29:37 pmnot really, if there is only one spark then it's the same as a one point plug unless your saying that the spark will occur where the mix is (presumably there will be less resistance on the electrode that gets to ignite)

author: SeanB
author_rank: Super Contributor
timestamp: August 22, 2012, 06:28:57 pm
content: No, the spark will still be random, but you have a 1 in 4 chance of it being in the right spot for immediate ignition and a perfect fire, as opposed to the other where it has to be at the right spot. It still burns, but the time is delayed somewhat by a few microseconds so this time it does not produce the best power.

author: NiHaoMike
author_rank: Super Contributor
timestamp: August 23, 2012, 01:26:21 am
content: Those "4 point" plugs are likely worse than regular plugs since there are 4 electrodes shading the combustion process instead of just 1. In fact, on engines where the spark plugs are not in the center, there is a slight efficiency increase aiming the electrode away from the center.What does make a difference is to put more peak power into the spark. The combustion process would then start sooner and more predictably (especially with lean mixtures) after the spark. There were some "premium" spark plugs that had integrated capacitors to increase the intensity of the spark. Unfortunately, they delayed the spark enough that the engine would run poorly. Someone who installed those plugs and adjusted the timing to compensate reported a good improvement in efficiency, but not enough to offset the price of the plugs.The 2011 Hyundai Sonata used a "two stage" ignition system (first step up 12V to an intermediate voltage like 100-400V, then step it up to several 10s of kV to fire the plugs) to get what was an unsurpassed MPG for a non hybrid car of that size. The idea is that higher voltage and lower current means stray inductance and resistance matter less, while the second transformer allows the use of affordable semiconductors as switches. Oddly enough, the Prius doesn't have that despite already having 200V under the hood, but I guess going from 50 MPG to 55 MPG or even 60 MPG would not gain enough extra sales or enough price premium to be worth the cost.

author: SeanB
author_rank: Super Contributor
timestamp: August 23, 2012, 05:12:35 am
content: Hyundai and Mercedes use a 36-40V internal rail, so as to have a higher charge current into the one coil per plug packs. A higher voltage output and a longer length of discharge so that the mixture will ignite eventually. Does lead to some instability in cylinder for spark to spark at very lean mixtures, but they all will ignite in the cylinder.I took one of those coils apart, 300 turn or so primary and a solid encapasulated secondary. Low inductance and direct over the plug

author: Simon
author_rank: Unknown
timestamp: August 23, 2012, 06:57:40 am
content: Quote from: NiHaoMike on August 23, 2012, 01:26:21 amNo ? 10-20% increase not worth it ? sounds like a bargain to me considering the lifetime of the car and the 10's of 1000's of miles it will do, (hopefully 100's of 1000's)

author: GK
author_rank: Super Contributor
timestamp: August 23, 2012, 10:50:17 am
content: Quote from: Uncle Vernon on August 22, 2012, 01:04:33 pmWhat the?Your comment was ambiguous and you did not write "removing the cat in isolation". Of course major exhaust mods will require a retune to be effective.

author: Unknown
author_rank: Unknown
timestamp: August 24, 2012, 12:00:02 am
content: Quote from: GK on August 23, 2012, 10:50:17 amThat's it! This whole thread is full of hopes of black magic, how 2 foot of plastic tube or some other bright idea is going to transform any povvo pack shopping car into a high HP monster with excellent fuel economy. It's not going to happen!There are no hidden 10% increases waiting to happen. No hidden plots by car manufacturers and fuel companies.Yes you can modify cars into very different character, but to it's an exercise in compromises, always was, always will be. And every modification brings about it's own set of compromises, any of them done in isolation is liable to make HP, economy or overall performance worse, not better.

author: NiHaoMike
author_rank: Super Contributor
timestamp: August 24, 2012, 01:33:23 am
content: Quote from: Simon on August 23, 2012, 06:57:40 amWith so little competition, Toyota probably felt that the incremental investment would not bring back enough return. To them, the difference between 50 MPG and 60 MPG is a car that sells well and a car that sells very slightly better. Things might have been different if GM continued making EV1 hybrids that got 80 MPG, or if the Insight got more than 50 MPG.The Prius does have the (presumably) flyback transformers and power stages in the same modules. Maybe that lets them get the same effect by reducing stray inductance and resistance.QuoteWas the 36-40V because of an (unsuccessful) attempt to move to a 42V electrical system? Given that they would need a DC/DC converter, it makes more sense to go directly to the 300V or so that is typical of such high energy ignition systems.

author: Zad
author_rank: Super Contributor
timestamp: August 24, 2012, 02:27:31 am
content: Modern ECUs have effectively "tuned" themselves for a long time. Are people really so unaware of ECU adaptation? Even the 1983 Ford EEC-IV was capable of adjusting various parameters to account for sensor degradation and engine wear. Yes, you can get custom engine maps, but on non-turbo cars these rarely offer more than 2% gain, and improvements in driveability (removal of over-run cutoff etc). They are pretty damn good at optimising.Way back in 1976, Volvo were using a Lambda sensor to detect the engine emissions and adjust the mixture to ensure it isn't too lean or too rich. Indeed, if you try to tweak any modern engine to run leaner by spoofing the airflow meter or whatever, the exhaust gas sensor will eventually ensure the mixture is servoed back to the pre-programmed stoichometric ratio, treating the user interference as a degraded sensor. The only exception being whilst the engine is warming up, and at wide open throttle. If you are foolish enough to force your engine to run lean for extended periods then you can expect a bill for new exhaust valves.There are some modern domestic engines which monitor pressure and oxygen across the catalyst, and might flag up a fault, but Endura is not one of them. Personally, I wouldn't bother de-catting, but people looking for that extra few percent in real performance cars do so.