HDTenEightyP/NetNews huggingface dataset:
From: dsr@chickpea.mitre.org (Douglas S. Rand)
Subject: Re: So what is octane, anyway?
Organization: The MITRE Corporation
Date: Thu, 9 Apr 1992 15:48:04 GMT

In article <1992Apr09.040437.62461@cs.cmu.edu> rudis+@CS.CMU.EDU (Rujith S DeSilva) writes:

   Forgive this novice question, but the on-going discussion on octane/power has really confused me.  I remember reading that a long time ago that the octane system was designed by:
	   o Assigning the value 0 to the worst known fuel (say BAD-FUEL)
	   o Assigning the value 100 to the best known fuel (say GOOD-FUEL)
	   o Calibrating other fuels against the above two.  For instance, if some
	     fuel was equivalent to a 30/70 mixture of BAD-FUEL/GOOD-FUEL, it was
	     assigned octane 70.
... rest of confusion deleted.

Not even remotely true.  Octane is a measure of a fuel to resist
detonation from spontaneous combustion on compression.  There are
different methods of measuring this and the number on the pump is a
mixture of these methods.  From websters:

octane number n (1931)
    :a number that is used to measure the antiknock properties of a liquid 
    motor fuel and that represents the percentage by volume of isooctane 
    in a reference fuel consisting of a mixture of isooctane and normal 
    heptane and matching in knocking properties the fuel being tested -- 
    called also octane rating; compare CETANE NUMBER

So higher octane is necessary for higher compression engines.  This
leads to a mistaken impression that higher octane fuels are more
dense in energy.  The truth is that higher compression engines are
more efficient (see the Otto cycle in a thermodynamics text) and
therefore extract more energy per unit of fuel.

--
Douglas S. Rand 
Internet:   <dsrand@mitre.org>
Snail:	    MITRE, Burlington Road, Bedford, MA 
Disclaimer: MITRE might agree with me - then again...
Amateur Radio: KC1KJ
From: keithg@hpdmd48.boi.hp.com (Keith Glasson)
Date: Thu, 9 Apr 1992 07:00:47 GMT
Subject: Re: Are '83 Subaru brake discs removable?
Organization: Hewlett Packard - Boise, ID
Newsgroups: rec.autos.tech

/ hpdmd48:rec.autos.tech / franz@cs.washington.edu (Franz G. Amador) /  7:03 pm  Apr  7, 1992 /
Does anybody know if the front brake rotors of an '83 Subaru GL wagon
can be removed for resurfacing?  _How_to_Keep_Your_Subaru_Alive_ says
they can, a local respected tire/brake/alignment shop says they can't.
The guy at the shop said, "A front brake job costs x, but, oops, your
car is a special case.  We can't take the rotors off, so we have to
machine them on the car, which means the job costs 4x [or something
like that]."

Obviously, given enough work, they must come off somehow.  How else
could you replace them?  Is there some sort of labor threshold
beyond which a shop will say they can't do it?

Franz Amador
franz@cs.washington.edu
{rutgers,cornell,ucsd,ubc-cs,tektronix}!uw-beaver!june!franz
----------
	I don't know why they wouldn't be removable. I have an '83 GL
	sedan, and yanking the rotors off is no big deal. It shouldn't
	be any different for a wagon, and as you said, they have to 
	come off somehow.
Newsgroups: rec.autos.tech
From: bishop@b23a.ingr.com (David Bishop)
Subject: Can you flood a fuel injected car??
Organization: Intergraph
Distribution: rec
Date: Tue, 7 Apr 1992 16:36:32 GMT


I am the owner of an 86' Mazda 626-GT (turbo) This car has been
a great one for me as I have had very few problems with it. 
I have a problem that has developed recently that is, to say the
least, annoying.  

 When I start the car when the engine is cold, I usually just
turn the key, without pressing the gas pedal, and the car starts
just like a properly tuned car should. However, lately I have 
done the same as always, cranking the car without first touching the gas,
and if the engine doesn't catch in the first 5-10 seconds, it just
won't crank at all.It turns over but it just won't crank. I have to wait
approx. 30 min. before I can get the thing to start. Now if I tap
the gas when I first crank it, it starts ok. 

 My question is, shouldn't a car crank without touching the gas?
 ( if it's properly tuned of course)
Secondly, it seems like the engine is flooded but how can that be if
I don't touch the gas when I first crank the car? If the engine is flooded,
why does it not crank when I hold the pedal to the floor like a carburated
engine would?
I guess I'm not sure about the differences between starting a car
 with a carb or one that's fuel-injected.

Any bright ideas are most appreciated. Thanx

*******************************************************************************
 David J. Bishop  (Electronic Pubs Support)                  When uncertain,
 Intergraph Corporation                                      and in doubt,
 ingr!b23a!bishop!david - david@bishop.b23a.ingr.com         run in circles,
 (205)730-8318  (digital beeper 720-1443)                    scream and shout
*******************************************************************************
Newsgroups: rec.autos.tech
From: ward@m.cs.uiuc.edu (Christ Ward)
Subject: Chevron Techtron and Engine Cleaner
Summary: Chevron Pro-gaurd vs Engine Cleaner?
Keywords: Techtron and 
Organization: University of Illinois, Dept. of Comp. Sci., Urbana, IL
Date: Wed, 8 Apr 1992 12:49:05 GMT

I desided to use the Techtron FI cleaner as recomended by the faq,
I just gota VW vanagon with 60,000, so I tought it would be a good
idea (people say this is the same stuff VW sales is this true?).

So I stop at one of those major discount auto  places...and after
looking around I find it.  But, Chevron has two products with
similar claims, I got the FI cleaner (Pro-guard with Techtron).
Whats with this other stuff?  They make similar claims to the FI
cleaner.  So whats the difference? Is the engine cleaner better
for carbs or what?  I got injectors so I'm going to stick to that
but I'd like to know....

thanks 

chris ward
q
Newsgroups: rec.autos.tech
From: johnson@wrs.com (David Johnson)
Subject: New Group. was  Re: Turbocharger VS. Supercharger.
Organization: Wind River Systems, Inc.
Date: Thu, 9 Apr 1992 23:19:15 GMT

Why don't we start up a new group called rec.autos.tech.help, because none
of these posts are helping at all.

I'll be the first to admit that these things can get out of hand.
I have mailed Walt T. explaining in full what my *real* gripe was about in      
the first place. All of this arguing is just a waste of time. It has        
turned from a gripe about the condescending nature of some veteran 
subscribers, into the age old grudge of "my supercharger can beat the &#%@!
out of your turbocharger!"  Sure we can bitch all we want, but are we 
accomplishing anything? If you want to bitch to someone just mail me the 
crap. I'll gladly delete the garbage faster than you can say pressurized
induction, but let's keep it off the net.

>DAVE   

From: borowski@hpspkla.spk.hp.com (Don T. Borowski)
Date: Wed, 8 Apr 1992 15:18:23 GMT
Subject: Re: Gets hot and dies...
Organization: Hewlett Packard Company, Spokane, Wa.
Newsgroups: rec.autos.tech

>In rec.autos.tech, bnbailey@ducvax.auburn.edu writes:
>
>    Folks--
>  I've got a 1950 Ford, with 4-cylinder L-head engine much like a Model
>A.  The electrical system is 6-volt.  I've got a problem with the engine just
>dying and not re-starting.  Here is the scenario--
>
>    I'll start the engine cold, and it starts fine (well, as fine as a
>six-volt system will start).  Runs great.  I'll let the vehicle warm up a
>little.  Just enough to get the oil warm and flowing well.  And then I'll 
>start work.  Use the vehicle under load for maybe 5 minutes, maybe 15 or 20.
>Then it just dies as if the coil wire were yanked off.  I've replaced the coil,
>by the way.  It's new and hot.  It won't re-start.  So, I walk to the house, 
>get a drink of iced tea, read my owner's manual a little while, then go back,
>and it it's nice a cool, it will start back up.  I'll drive it to its parking
>place, and it will cough a time or two on the way.  Then I'll shut it down, and 
>scratch my head awhile. 
>
>    Another possibly related symptom--it knocks (pre-iginites) like hell
>under load.  Not necessarily under heavy load, either.  As if there were no
>spark advance.  
>
>   As I mentioned, I have replaced the coil.  This seems to be
>spark-related, and I think plugs-points-condenser-wires would do the trick.  I 
>am afraid that the distributor needs work.  Does anyone have any thoughts on 
>this?  I'm not a mechanic, but will have to do the work myself due to lack of 
>funds, so I want to get as much background as I can before I start.  Am I 
>overlooking something obvious?

Certainly, new plugs,points, condenser, and wires are a good start.  If you
want, you might do some trouble shooting next time the engine dies.  Pull
the wire from the coil to the distributor off at the distributor end, hold
it near come metal, and crank the engine.  See if the spark is nice and fat.
Reconnect the wire, and do the same with each spark plug wire.

For the knocking problem, get a timing light, and check the timing.  See
if it advances at higher rpms, and then retards again at lower revs.  Also,
pull the vacuum line of the distributor and see if the timing retards, and
advances again when you put the line back on.


Donald Borowski    WA6OMI    Hewlett-Packard, Spokane Division
"Angels are able to fly because they take themselves so lightly."
                                       -G.K. Chesterton
From: ADVI8715@RyeVm.Ryerson.Ca (Pars Sewgobind)
Newsgroups: rec.autos.tech
Subject: Speed Limiters on a 1989 Chevy Corsica
Date: 15 Apr 92 22:58:40 GMT
Distribution: na
Organization: Ryerson Polytechnical Institute

Hi,
   I own a  Black 1989 Chevrolet Corsica LT.  It's GM's 3.1 V6 EFI engine deliv
ering 140bhp at 3200rpm.  And a max torque of 186 fp.  Anyways, the car will ac
celerate all the way to  185km/h and then all of a sudden it cuts out.  Yeah, I
 know that's a speed limiter, probably 'cause of speed rated tires and maybe ev
en the suspension.  Right now I have GoodYear  GT+4's on all four wheels.  Does
 ANYONE OUT THERE know a way of getting rid of the speed limiter, a friend sugg
ested pulling one of the fuses, but I think I tried all of them and nothing see
ms to do any good.  Maybe I missed something.
 The thing that bugs me is the car has alot of power left even at cutout, at 18
5km/h, I mean you can feel her pull all the way upto that point.  I really pity
 someone with a 5.0L Mustang who has the same problem, what a waste of car :)

 Hope to hear something from someone soon..  Thanks


Speed (advi8715@ryevm.ryerson.ca)
      (ADVI8715@RYERSON.BITNET)
From: gss@btcase.bt.co.uk (Graham Sewell)
Newsgroups: rec.autos.tech
Subject: Re: So what is octane, anyway?
Date: 9 Apr 92 12:53:20 GMT
Organization: British Telecom, Lion House, London.

rudis+@CS.CMU.EDU (Rujith S DeSilva) writes:

>Forgive this novice question, but the on-going discussion on octane/power has really confused me.  I remember reading that a long time ago that the octane system was designed by:
>	o Assigning the value 0 to the worst known fuel (say BAD-FUEL)
>	o Assigning the value 100 to the best known fuel (say GOOD-FUEL)
>	o Calibrating other fuels against the above two.  For instance, if some
>	  fuel was equivalent to a 30/70 mixture of BAD-FUEL/GOOD-FUEL, it was
>	  assigned octane 70.

>Later, better fuels than GOOD-FUEL were found, and these have been logically
>assigned octane ratings greater than 100.

>Is this basically correct?  If so, what were BAD-FUEL and GOOD-FUEL?  By what
>criterion were they the worst/best at the time?  Are the mixtures I referred to
>by weight or by volume, and by what criterion was the mixture considered
>`equivalent' to the fuel being calibrated?  If not, what is octane anyway?

If I remember correctly:

GOOD-FUEL  equates to OCTANE	(C8H18)
BAD-FUEL   equates to HEPTANE	(C7H16)

-- 
Graham Sewell                          Tel   +44 71 728 4851
Unix TP and Database Unit              Fax   +44 71 728 4883
PP506, Lion House, 72-75 Red Lion St, LONDON. WC1R 4RT
gss@btcase.bt.co.uk
Newsgroups: rec.autos.tech
From: sbender@navajo.dsd.es.com (Steve Bender)
Subject: Re: temperature gage and fuel gage problem
Organization: Evans & Sutherland
Date: Tue, 14 Apr 92 15:05:36 GMT

In article <1992Apr7.130034.2709@usenet.ins.cwru.edu>, bi927@cleveland.Freenet.Edu (Yi Jin) writes:
|> 
|> This morning. My 83 Honda Accord had some problem with the fuel gage and 
|> temperature gage. After 5 minutes driving, both the temperature gage and
|> fuel gage went full, I.E, the gages indicated that temperature was overheated
|> and fuel was full, although the fuel tank was near empty. However, safter 
|> several turn-off turn-on tries, the gage seems normal now. What that 
|> problem could be? Is that only the gage problem, or there are something 
|> wrong with the system.?
|> 
|> The coolant was full and the thermostat was changed last year. What else
|> should I check.
|> 
|> Thanks for help.

It is likely that the two guages share the same ground connection and
that connection is interrupted.  If you can get your hands on one, get
a wiring diagram and begin following the guage(s) ground backward from
the guages to the chassis/engine.  Also check that your engine is
properly grounded to the chassis via a ground strap...  After time, 
these can corrode/fail and cause numerous frustrations and problems.

-- 
Steve Bender
Evans & Sutherland
(801) 582-5847
Salt Lake City, UT 84108

sbender@dsd.es.com

Newsgroups: rec.autos.tech
From: floyd@eng.umd.edu (Mike Hughes)
Subject: Re: G.M. (late model) pickups (ROAR)  
Date: Thu, 16 Apr 92 16:58:46 GMT
Organization: University of Maryland

	The 'roar' heard on many larger vehicals upon initial start-up is just
the cooling fan.  The larger cars and trucks are now the only ones with lon-
gitudinally mounted engines and belt-driven cooling fans.  The fan is coupled
to the belts (usually bolted on the front of the water pump pulley) via a fluid
filled clutch.  This clutch slips, allowing the pulley to spin faster than the
fan when the engine is cold.  When the air flowing through the radiator is hot,
the clutch locks up and forces the fan to spin faster.  

	The clutch is filled with silicon, and when it doesn't spin, the sili-
con flows where it's not supposed to be.  So, when the engine starts, the
fan clutch is locked, and the fan spins fast.  After a few seconds, the fluid
is distrubuted more uniformly, and the clutch allows the fan to slow down.  
When the fan clutch is locked, there is *QUITE* a difference in power (the fan
requires a *LOT* of HP to spin at 1500 RPM).

	The clutch on my '76 280Z locked up (internal bearing failure) on my
sister when she was on the highway.  She came back telling me that something
was making a real loud 'power-like' noise, and it seemed like the car didn't 
have much power.  I'm suprised the belt was able to spin that without slipping!
-Mike

:Suicidal Tendencies=====> He's a carrier of death a stork in reverse,        :
: =8^) Mike Hughes  =8^( : he blesses you with sickness cause love is a curse.:
:Mail---floyd@eng.umd.edu: The arsenic in your Koolaid, the bomb in your mail,:
:Voice--(301) 340-0922   : he disappears in motion but leaves a bloody trail. :
Newsgroups: rec.autos.tech
From: tedebear@leland.Stanford.EDU (Theodore Chen)
Subject: Re: Question on affect of caster, camber, toe. (Mustang 5.0)
Organization: DSG, Stanford University, CA 94305, USA
Date: Wed, 8 Apr 92 07:29:24 GMT

In article <10241@inews.intel.com> pharvey@mipos3.intel.com (Paul Harvey) writes:
>In article <1992Mar29.103852.20453@mintaka.lcs.mit.edu> lusky@hal.gnu.ai.mit.edu (Jonathan R. Lusky) writes:
>>(0 degrees) and wearout the outside edges of their tires very rapidly due to 
>>their driving styles. One of them finally set the camber as negative as it 
>>would go on his 89 LX and his tires now wear flat (and yes, he does happen 
>>to autocross on his street tires...).
[inserted CR-LFs to improve readability]
>Yeah, but how negative is "as negative as it would go"? I'm guessing that
>it's probably about -1 without mods. 
>And your friends would probably get better 
>traction during Xcross with a degree or two
>more. Better yet, tell your friends
>to drive smoother, they're probably scrubing
>too much. These cars have Mac-strut 
>front ends, right? So the problem with
>this suspension is that in order to get 
>no net camber change with body roll, the
strut has to be angled some 60 degrees.

actually, it's a modified macpherson strut setup (that's what the
service manual calls it).  i changed the struts a few years ago...
as i remember, it was not a coil over strut setup.
can't remember the relative locations, but the strut wasn't inside
the coil.  dunno why it's still called a macpherson strut, though
(maybe somebody can enlighten me on that).

another thing i don't understand.  where did you get the 60 degree
figure?  i realize that there's body roll and the struts need to be
at some angle to compensate for that, but i don't know where 60 comes from.
is this just for the mustang?  wouldn't it depend on the stiffness of
the coil springs?
-teddy
From: ai065@cleveland.Freenet.Edu (Thomas Hill)
Newsgroups: rec.autos.tech
Subject: Re: Engine Temp Quickly "Surges" Up & Down
Date: 9 Apr 92 18:03:01 GMT
Article-I.D.: usenet.1992Apr9.180301.10390
Organization: Case Western Reserve University, Cleveland, Ohio, (USA)


   The fluid level is fine. The last time it did it the gas gage also went
up a bit, so I'm convinced this is some type of electrical problem. Only
problem is finding out what. Ideas?
-- 
    __ This ISN'T about lazy Americans. This ISN'T about being uncompetitive.
 __/// This ISN'T about Japan bashing.          This ISN'T EVEN about racism.
 \XX/  THIS *IS* ABOUT OPEN MARKETS AND JAPAN DOESN'T HAVE ONE!  BOTTOM LINE!
       The Cryptozoology Information Network  Want on our Email mailing list?
From: georgej@gtephx.UUCP (Jefferson George)
Newsgroups: rec.autos.tech
Subject: monza exhaust system
Keywords: monza
Date: 10 Apr 92 21:27:06 GMT
Distribution: na
Organization: AG Communication Systems - Phoenix, AZ

I am thinking of getting a MONZA exhaust system for my
wife's 84 Celica.  Any good/bad experience with this
brand.  I received a fax on how the system looks like.
It connects to the catalytic converter and has a
dual tip existing the muffler.

thx



-- 
Jefferson George                                    
AG Communication Systems, Phoenix, Arizona 
Inet: gtephx!georgej@asuvax.eas.asu.edu   
UUCP: {ncar!noao!asuvax | att}!gtephx!georgej 
Newsgroups: rec.autos.tech
From: jmansfie@zeus.calpoly.edu (Jason Mansfield)
Subject: 500cid Eldo power prob
Organization: California Polytechnic State University, San Luis Obispo
Date: Mon, 13 Apr 1992 20:36:50 GMT

	First of all, thanx for all the replies.  But I still haven't solved
the problem.  It turns ou the timing was advanced about 3 degrees which
apparently makes a huge difference in that car (creating tons of black smoke).
So now it's at stock, but it's still gutless, running only a little rich, and
idles roughly.  I've considered all your suggestions and did a few more tests.
Im first giong to replace the muffler (it's shot anyway) which I figure could
be causing the rough idle and maybe the power prob due to restrictions (even
though the exhaust coming out of the tail pipe are quite strong.  I checked
the vacuum test again - it's now 14 psi.   I think that's way bad.  Could that
be caused by an exhaust restriction?  Oh, the EGR is fine BTW.  So is the
vacuum advance.  And there are no vacuum leaks that I can find.  People have
suggested a worn cam, but that was the case, there would probably be other
worn engine parts resulting in an oil thirsty engine (which it isn't THAT
bad).  So any further suggestions?  Could it just be the muffler?  I have
to wait 10 days for a muffler to be ordered (I guess they have to go mine
the ore and everything to get stuff to make a big enough muffler :^)) and
I don't want to drive around with a very loud exhaust until then so I
haven't tested the car with it off.
	Thanx for all your help.

	- Jason - jmansfie@athena.calpoly.edu - The Cadillac man -
From: c.oneill@trl.oz.au (Chris O'Neill)
Newsgroups: rec.autos.tech
Subject: Re: *** EFFICIENT DRIVING TIPS FOR STICK SHIFT ? *****
Date: 13 Apr 92 00:45:44 GMT
Organization: Telecom Australia Research Laboratories

In article <1992Apr6.020243.14152@ccad.uiowa.edu> laughlin@ccad.uiowa.edu (John
Laughlin) writes:
>In article <1992Apr3.183440.13756@news.iastate.edu> plakshm@iastate.edu (P G
Lakshminarayan) writes:
>>I bought a used 82 Nissan Stanza with manual transmission, for the first
time.
>>I didn't get the manual.  Since I am new to manual transmission I have few 
>>questions.
>>
>>1. To get best gas mileage what is the speed ranges at which I should shift
to
>>higher gears.
>
>To get the best milage, coast as much as possible and try to time your
>driving so you never have to stop for a red light.  Higher (4th or 5th) gear
>can be used at low speeds as long as you do not lug the engine.  In other
>words, try to shift as soon as possible, but don't try to accelerate 
>when you are going slow and are in a higher gear.

"as soon as possible" needs to be precisely defined.  It means either
(1) when you reach your rev limit (not the redline) or
(2) when you are no longer accelerating.

The important point is that it is wrong to shift up prematurely if you still
want to accelerate.  The commonly known "most efficient gear for a certain
speed" only applies to a car driven at constant speed.  When the car is
accelerated, the most efficient gear depends on the acceleration as well as the
speed.

The most efficient way to accelerate a car to a certain speed is to accelerate
up to a certain number of revs in each gear and to hold the throttle to give
something around 200mm of manifold vacuum.  When you reach the required speed,
you change to top gear (as long as you are not going up a steep hill).

The choice of revs at which to shift up is not very exact.  This is because the
maximum engine efficiency (with respect to throttle variation) does not vary
much with revs over the normal rev range.  Hence you can achieve best fuel
economy without restricting gear changes to narrow speed ranges.  The fuel
economy during acceleration depends much more on throttle control than on the
speeds chosen for gear changes.

Chris O'Neill
Newsgroups: rec.autos.tech
From: jgd@dixie.com (John De Armond)
Subject: Re: Freon Freeze!
Date: Mon, 06 Apr 92 15:39:11 GMT
Organization: Dixie Communications Public Access.  The Mouth of the South.

c.oneill@trl.oz.au (Chris O'Neill) writes:

>>Hydrocarbons (e.g. isobutane/propane)
>>Have been used for years at refineries, and other applications which deal
>>with flammability, etc.  Works well as a refrigerant.  A blend of
>>21% isobutane and 79% propane (by weight) is a good drop-in for R-12.

>Liquified petroleum gas (LPG) powered vehicles are quite common in Australia,
>perhaps not so common in the US.  Does anyone know if a hydrocarbon charged
>air-conditioner is any more dangerous than an LPG tank and supply system.

Let's see.  An auto air conditioner will hold a pound or less of this
stuff.  Essentially all the piping other than the evaporator is forward
of the fire wall.  LPG powered vehicles have from 100 to 150 lbs of propane in
the trunk/truck bed.  A liquid line runs the length of the vehicle under
the cab to the vaporizer and then to the carb.  

Nah, I don't think a pound of isobutane/propane is dangerous in that (or
any other setting).  

John
-- 
John De Armond, WD4OQC        | "Hey, don't blame me.  I voted Buchanan."
Rapid Deployment System, Inc. | 2nd Amendment RADICAL 
Marietta, Ga                  |              
jgd@dixie.com                 | Need public access in Atl?  Write me.
Newsgroups: rec.autos.tech