Newsgroup: it.discussioni.auto
Titolo: Tutto ma proprio tutto sulla nuova GT3 (Inglese e lungo)

More power and more torque on the same engine size and with unchanged fuel
consumption – this, in a nutshell, describes the development formula for the
second-generation 911 GT3. Consistently reducing moving masses in the
six-cylinder power unit and capitalising on the benefits of infinite
VarioCam camshaft adjustment, the new 911 GT3 comes with a significant boost
in power of 15 kW or 21 bhp: Maximum output is up from 265 kW or 360 bhp at
7200 rpm to 280 kW or 381 bhp at 7400 rpm. Maximum torque has increased from
370 to 385 Newton-metres (272-284 lb-ft) at unchanged engine speed of
5000rpm.
In the process the six-cylinder power unit has also improved even further in
its free-revving running qualities, engine speeds moving up even more
dynamically and maximum engine speed increasing accordingly: Now engine
control does not take over in the lower four gears until 8200 rpm, as
opposed to 7800 rpm in the past. On the road, this improvement of
free-revving qualities offers an over-proportional increase in actual
performance you can both feel and measure: The 911 GT3 accelerates to 100
km/h from a standstill in just 4.5 seconds, 0.3 seconds faster than before.
And now, also benefitting from even better streamlining, the new model
continues to surge ahead all the way to a maximum speed to 306 km/h or
190mph.
Brake system now featuring ceramic discs
The supreme qualities of the 911 GT3 in terms of acceleration, flexibility
and top speed are matched just as convincingly by the car's stopping power
and deceleration to master the even greater power of the engine and the
car's dynamic performance enhanced to a new level by the optimised chassis
and suspension. The front brake discs have been increased in diameter by 20
millimetres to the new dimension of 350 millimetres or 13.8". And compared
with the previous model featuring four-piston fixed callipers, the new 911
GT3 comes with far more powerful six-piston brake callipers finished by
tradition in red. These callipers enlarge the contact area between the brake
pads and the brake discs by approximately 40 per cent, ensuring outstanding
deceleration and stopping power even under the toughestconditions.
As an option the new 911 GT3 may be equipped with Porsche Ceramic Composite
Brakes (PCCB). Cross-drilled and inner-vented, these ceramic composite brake
discs measuring 350 millimetres in diameter are 50 per cent lighter than
metal brake discs and reduce unsprung masses by approximately 18 kg. In
conjunction with the brake lining also developed specifically for this
model, the ceramic brake discs immediately ensure a very high and, in
particular, consistent frictional coefficient throughout the entire
brakingprocess.
Streamlining better than ever before
Improving the aerodynamic qualities of the 911 GT3 in virtually every
respect, Porsche's engineers and aerodynamicists have focused on each and
every millimetre of the car's outer skin in the interest of maximum
performance. Particularly striking points are the newly designed front end
with its enhanced swept-back nose and the new side-sills as well as the
truly dominating rear spoiler. These are the main reasons for the ongoing
reduction of lift forces on both the front and the rear axle, without any
change in the drag coefficient of 0.30. Featuring a 40-millimetre-wide
spoiler “lip" extending round the entire front end, the new front bumper
cover significantly reduces the flow of air beneath the car. The optimum
position of the cooling air intakes, in turn, feeds a large share of the air
coming out of the radiators at the side directly to the brake system, and
not beneath the car, thus helping to significantly reduce front axle lift.
The new Porsche 911 GT3
The Purist Sports Car
The new Porsche 911 GT3 comes with all the features of half a century
Porsche motorsport. It is a sports car for the purist through and through. A
sports car with all the classic virtues a car of this kind is expected to
have – and without all the ballast which might in some way impair your
outstanding driving experience. The new 911 GT3 is not “just" a two-seater
coupé homologated for the road and taking you to work reliably every day
without the slightest problem. No – it is also a sports car allowing lap
times on the race track one would never expect of a street-legal road car.
And for the first time the new 911 GT3 is also available in the USA.
The engine – even more power and performance
Developing 280 kW or 381 bhp, the 3.6-litre six-cylinder power unit fitted
in the rear offers almost 10 per cent more output for a truly supreme
driving experience. Output per litre of 77.8 kW or 105.8 bhp makes this
3.6-litre flat-six one of the topmost normal-aspiration engines in the
world. Benefitting also from streamlining improved to an even higher
standard, top speed is now 306 km/h or 190 mph. Maximum torque, finally, is
up from 370 to 385 Newton-metres (272 – 284lb-ft).
This further improvement of power and performance is a result of Porsche's
consistent high enginespeed concept based on the reduction of moving masses
in the engine. A further reason for the increase in output developed by the
GT3 power unit is the introduction of infinitely controlled intake camshaft
management well known as Porsche VarioCam. The green area in the rev
counter, in turn, now extends up to 8200 rpm, 400 revs more than before.
This provides significant benefits particularly in terms of acceleration,
the new 911 GT3 accelerating from a standstill to 100 km/h in just 4.5
seconds, 3/10ths of a second faster than its predecessor. But despite this
enhanced performance, the new 911 GT3 consumes only 12.9 litres (21.9 mpg
Imp) in the EU composite cycle, that is exactly as much as its predecessor,
whilst naturally outperforming both the EU4 and the LEV emission limits.
Precisely shifting six-speed gearbox
The new, even more dynamic power unit of the 911 GT3 forms a perfect team
with the six-speed gearbox enabling the driver to enjoy the agility of this
six-cylinder particularly at high speeds. With a transmission ratio of 1.00
and, respectively, 0.85, fifth and sixth gear have a slightly shorter ratio
than before (previously 0.97 and, respectively, 0.83). The introduction of
splash oil lubrication and the new external transmission fluid cooling
system also show how carefully the gearbox has been prepared for the
toughest motorsportrequirements.
Exemplary deceleration
Incorporating new, wider but nevertheless lighter wheels, the sports chassis
allows even faster longitudinal and lateral acceleration than before.
Developed especially for the 911 GT3, the tyres come on new rims bearing the
GT3 logo on the wheel hub cover. Tyre dimensions at the front are 235/40 ZR
18 on 8 1/2" rims, the rear tyres measure 295/30 ZR 18 on 11"rims.
The brake system featured in the 911 GT3 is an ongoing development of the
brake system carried over from the former model, now boasting 350-millimetre
(13.8") brake discs and six-piston fixed calliper brakes at the front. The
rear wheels, in turn, feature four-piston brake callipers teaming up with
330-millimetre (13.0") brakediscs.
As an option the 911 GT3 is available with Porsche Ceramic Composite Brakes
(PCCB). The cross-drilled, inner-vented ceramic composite brake discs
measuring 350 millimetres in diameter weigh 50 per cent less than metal
brake discs and reduce unsprung masses by approximately 18 kg. In
conjunction with the brake lining also developed specifically for this new
model, the ceramic brake discs ensure a very high and, in particular,
consistent frictional coefficient throughout theirapplication.
Aerodynamically balanced all the way to top speed
The new 911 GT3 confirms in every respect the sporting impression it offers
at very first sight. Each and every millimetre of the car is designed and
built for maximum performance. Particularly striking points are the newly
designed front end swept back back at a steeper angle, the newly designed
side-sills, and the powerful-looking rear spoiler. Expressing this in
figures, the 911 GT3 has a drag coefficient of 0.30 truly outstanding for a
car of this type. And although this figure is the same as on the previous
model, lift forces on the front and rear axle have been reduced once again.
The result of this front-to-rear lift balance matched perfectly to the
chassis and suspension is truly outstanding driving characteristics offered
by the new 911 GT3 also at topspeed.
Sporting cockpit
Not just the exterior, but also the interior of the Porsche 911 GT3 leaves
no doubt that the driver and co-driver are enjoying the qualities of a
thoroughbred sports car. Leather-covered bucket seats made of a high-quality
synthetic material guarantee not just optimum side support, but also a very
high standard of comfort even on long distances. And they provide a
reduction in weight by about 20 kg versus the seats in the 911 Carrera. To
further optimise vehicle weight, the 911 GT3 comes without rear seats, again
saving 8 kg.
It almost goes without saying that driver, passenger and side airbags as
well as electric window lifts, an immobiliser complete with transponder,
central locking with remote control, and an alarm system, to mention only
some features, are standard equipment on the 911 GT3. Air conditioning with
an activated charcoal filter is available as a no-cost option. And to meet
the owner's individual wishes, finally, a wide range of options is also
available, such as bi-xenon headlights or complete preparation for
installation of a cartelephone.
The New Porsche 911 GT3
An Athlete with Even More Muscle
Porsche has sent its outstanding athlete to the training camp in Weissach,
Porsche's Motorsport Division, and in return has received an even more
powerful, sporting and dynamic 911 GT3. Developing 280 kW or 381 bhp, the
six-cylinder fitted at the rear offers an increase in output of almost 10
per cent. Output per litre of 77.8 kW or 105.8 bhp makes this 3.6-litre
flat-six one of the highest-performing normal-aspiration engines in the
world, giving the 911 GT3 a top speed of 306 km/h or 190 mph. The 911 GT3's
power-to-weight ratio clearly confirms that this horizontally-opposed
six-cylinder comes in a thoroughbred sports car: 3.6 kilos/bhp in road trim
complete with fuel and the driver is truly outstanding. Featuring new, wider
but nevertheless lighter wheels, the sports suspension not only offers even
better longitudinal and lateral acceleration, but is also able to get the
even greater power of the brakes on to the road safely and securely. As an
option, stopping power is provided by ceramic brake discs also available
from Porsche on the 911 GT3: Porsche Ceramic Composite Brakes or PCCB
forshort.
This further improvement of power and performance is ensured by consistent
application of the high-speed engine concept: High engine speeds are the
prerequisite for a high level of specific engine output and performance on
the road. The reduction of specific loads acting on the various components,
in turn, is the prerequisite for such high engine speeds, with the reduction
of moving masses in the engine being one of the crucialfactors.
The green area in the rev counter now extends all the way to 8200 rpm, 400
rpm more than before. This benefits above all the car's acceleration, the
option to shift gears at a later point allowing the driver to capitalise on
engine power and reduce the power gap when shifting down to higher follow-up
revs. Expressed in figures, this means that the new 911 GT3 accelerates from
a standstill to 100 km/h in 4.5 seconds, 3/10ths of a second faster than its
predecessor. And this higher standard of performance is clearly borne out in
the car's ongoing acceleration to 160 km/h, the new 911 GT3 completing this
exercise in just 9.4 seconds as opposed to 10.2 seconds in the past. This
does not mean, however, that the new power unit in the 911 GT3 has to rely
on engine speed alone. On the contrary – the driver enjoys at least 80 per
cent of the engine's maximum torque from just 2000 rpm, thus benefitting
from ideal conditions for driving leisurely with substantial power reserves,
without shifting gears in theprocess.
The steel foundation for the bodyshell of the 911 GT3 comes as before from
the 911 Carrera 4. To match the enhanced performance of this new sports car,
the bodyshell has been further reinforced at all essential points, thus
offering an even higher standard of passive safety and enabling the new 911
GT3 to pass all the requisite crash tests with flying colours. At the same
time these reinforcements serve to increase static torsional stability by no
less than 25 per cent, providing ideal conditions for stable roadholding and
exact suspensioncontrol.
Enhanced by Porsche's motorsport specialists to the highest standard, the
new 911 GT3 offers a level of driving dynamics only a thoroughbred sports
car is able to provide. And this pure driving experience remains untouched
by any suspension control systems, with all components being designed and
coordinated for the toughest demands when driving on a race track. Indeed,
various components on the suspension and the car's streamlining may be
adjusted individually for motorsportrequirements.
Engine and Transmission
Even Less Mass – Even More Class
With engine displacement and the compression ratio remaining unchanged at
3600 cc and, respectively, 11.7:1, engine output is up from 265 kW (360 bhp)
at 7200 rpm to 280 kW (381 bhp) at 7400 rpm. Maximum torque has also
increased from 370 to 385 Newton-metres (272 to 284 lb-ft) at the same 5000
rpm as before. The reasons for this improvement is quite literally the light
weight of the car and engine. Consistent reduction of moving masses within
the power unit reduces the power loss, with an extra 15 kW or 21 bhp
reaching the flywheel. At the same time the six-cylinder revs up even more
smoothly and quickly than before, with even greater dynamic performance and
a higher cut-off speed: Instead of the previous speed limit of 7800 rpm,
engine management now allows the first four gears to rev up all the way to
8200 rpm, with a speed limit of 8000 rpm on fifth and sixth gear. The speed
limit on top gear is more of theoretical significance, since the 911 GT3
reaches its top speed of 306 km/h or 190 mph at approximately 7600 rpm. In
gears 1 – 4 the higher cut-off speed up over the former 911 GT3 by 400 rpm
provides an over-proportional increase in performance you can clearly feel
and even measure, the new 911 GT3 accelerating from 0 – 100 km/h in 4.5
seconds, that is 0.3 seconds faster thanbefore.
Lightweight pistons and connecting rods
Particularly the pistons and connecting rods as well as the valvetrain
benefit from this efficient “diet" of the engine's moving masses: Weight of
the forged pistons is down thanks to the lower height of the piston jackets
by 24 to 404 grams per piston. The piston pins, in turn, are made of a new,
high-strength material allowing more slender dimensions with the same
strength as before and therefore reducing pin weight from 120 to 96 grams.
Overall weight of the six new pistons is 3000 grams, 288 grams or almost 9
per cent less thanbefore.
Lightweight technology in design and the materials used also serves to
reduce the weight of the connecting rods. Although they now measure 130
millimetres or 5.12" in length instead of the former 127.8 millimetres or
5.03", the connecting rods are down in weight from 420 to 418 grams,
primarily thanks to precision forging and shot-peening of the titanium
connecting rods. With the new connecting rods and pistons allowing an
improved flow of forces to the crankshaft, Porsche's engineers were able to
diospense with the usual vibration damper on the crankshaft, again saving
more than 2 kg in rotating masses and helping to further enhance the
free-revving performance of the six-cylinder power unit. In all other
respects the crankshaft of the 911 GT3 running in 8 bearings and finished by
plasma-nitriding remains unchanged. The elaborate plasma-nitrided finish
incidentally ensures extremely strong and stable surface qualities around
the connecting rod and main bearing journals, achieving a standard otherwise
offered only by racingengines.
Infinite VarioCam for more power and greater fuel economy
Another reason for the increase in power and performance of the GT3 engine
is the introduction of infinite intake camshaft adjustment well known as
Porsche VarioCam. With this technology the angles on the intake camshaft are
adjusted by helical gearing inside the sprocket, which also houses a
helically-geared piston connected to the crankshaft and moved axially by oil
pressure. This turns the crankshaft by up to 450 against the sprocket,
modifying valve timing accordingly. And unlike the engine in the former
model where valve timing was varied by only 250 between the two terminal
positions, any angle may now be set as required. This larger adjustment
range naturally ensures even finer tuning of engine characteristics in terms
of output, torque and emissionmanagement,
Lighter valvetrain allows high engine speed concept
In support of the new engine's high speed concept, each moving component in
the cylinder charge cycle was weighed once again with utmost precision in
search of further weight reduction. As a result, the plates on the steel
intake and outlet valves now come with a dome-shaped profile, the valves
shedding 19 per cent or, in absolute terms, 252 grams grams of their
previousweight.
Reduced in diameter from 33 to 28 millimetres (1.30 – 1.10"), the newly
developed cup tappets serve to take another 21 grams per tappet (42 per
cent) off the engine's moving masses, cutting approximately 0.5 kilos more
off the total weight of the valvetrain. A special feature of the tappets is
their ball-shaped bottom curved like an arch to the outside. This special
design of the tappet:cam contact surface is the prerequisite for reducing
the diameter of the tappets, making the side contact surface even smaller
thanbefore.
The cams themselves have even “sharper" contours, opening the valves more
quickly and with higher lift. Again, this improvement of gas flow was made
possible without paying the price of greater wear – by the change in cup
tappet design to the ball shape just mentioned. The surface of the tappets
is specially hardened inter alia by carbon nitriding, reducing friction and
the need for lubrication and thus again helping to cut back the flow of oil
required. To ensure, finally, that the valves close properly despite
performance-optimised valve timing and the consequential increase in forces,
dual valve springs are used in the new engine asbefore.
New ME 7.8 engine management with E-gas
Featuring ME 7.8 engine management, the 911 GT3 comes with the most
sophisticated and highly developed Porsche engine management system. Apart
from “classic" features such as single coils in the high-voltage ignition,
sequential intake manifold injection, double lambda control and anti-knock
management, ME 7.8 serves inter alia to mastermind the throttle butterfly
via the E-gas and infinite VarioCam control systems. Being separated from
one another, the gas pedal and throttle butterfly help to optimise both fuel
consumption and emissions, without any effect on the engine's immediate
response to the driver's commands, the six-cylinder following even the
slightest movement of the gas pedal directly andinstantaneously.
Multi-component basic engine for motorsport
The basic engine is largely identical to the former power unit of the GT3 in
sandwich design, with the cylinder housing, cylinder head and crankshaft
housing combined with one another to form one unit for the three cylinders
on each side and increase the torsional stiffness of the engine accordingly.
Contrary to the engine in the 911 Carrera, therefore, the cylinder housings
are not connected to the respective section of the crankcase on each side,
but rather form separate units. The reason, quite simply, is that the engine
of the GT3, as in the past, provides the foundation for homologating
motorsport engines, meaning that Porsche has chosen this most elaborate
structure in order to respond very quickly to any changes in motorsport
regulations involving, say, the size of the engine. The cylinder liners
featured in the light-alloy cylinder housing are made of aluminium and are
coated with Nikasil. The cylinder heads, in turn, are made of an extremely
temperature-resistant lightalloy.
Another clear pledge to the motorsport orientation of the 911 GT3 is dry
sump lubrication with a separate oil tank. Both when applying the brakes to
the extreme and remaining on the brakes consistently for a long period, this
system ensures an optimum supply of oil to the engine, with a total of five
pumps ensuring the necessary lubrication: The main pump in the crankcase
feeds oil to the pressure pipes, two suction oil pumps in the crankcase and,
respectively, in the cylinder heads feed the oil used back into
thereservoir.
Performance-oriented fresh air and emission control
The power unit of the Porsche 911 GT3 draws in combustion air through an air
filter without an intake funnel. The resonance intake system made of light
alloy and featuring shorter intake manifolds, in turn, operates in two
stages: The resonance flap remains closed in the speed range between 2500
and 5500 rpm, with long intake travel providing high torque. Beyond 5500 rpm
the resonance flap is opened in the interest of maximum power.
The exhaust system is basically the same as on the 911 Carrera, meaning that
it comes in twin-chamber design, exhaust gas from the left- and right-hand
row of cylinders flowing back separately. Each of these exhaust pipes comes
with a lambda control oxygen sensor arranged upstream of the metal-based
catalytic converter, double lambda control of this quality reliably
fulfilling the strictest emission legislationworldwide.
Outperforming the EU4 and LEV standards
Infinitely variable VarioCam enables Porsche's engineers not only to
optimise the development of power and torque, but also to significantly
improve the engine's emission control. The raw gas flowing into the
catalytic converter comes with such a high standard of quality that the new
catalytic converter does not even need the usual layer of platinum.
Supported by a secondary air pump, the six-cylinder power unit of the 911
GT3 fulfils both the European EU4 and the US LEV emissionstandards.
Fuel economy remaining unchanged
Conceived as a high-performance power unit, the flat-six engine is designed
to ensure optimum energy yield, which naturally calls for fuel of the
highest quality: The engine reaches its maximum output on 98 octane premium
plus petrol. Thanks to anti-knock control, however, the 911 GT3 can also be
run without problems on less knock-resistant fuel grades down to regular
petrol with 92 RON. The power unit also achieves its highest standard of
fuel economy on premium plus, although fuel consumption tests are conducted
with standardised fuel equal to 95 octane premium. In the EU composite
consumption test, the new 911 GT3 consumes 12.9 litres on 100 km equal to
21.9 mpg Imp, which is exactly the same level of fuel economy as its
predecessor, a marginal increase in fuel consumption in urban traffic being
set off by the same reduction in fuel consumption when driving out oftown.
Shifting gears like in motorsport
The new, even more dynamic power unit of the 911 GT3 is matched perfectly by
the six-speed gearbox enabling the driver to make optimum use of the
engine's agility particularly at high speeds: At 1.00 and, respectively,
0.85, fifth and sixth gear have a somewhat shorter transmission ratio than
the previous gear ratios of 0.97 and, respectively, 0.83. And apart from
this change in gear ratios, the synchronising rings on the third, fourth and
fifth gear are now made of steel, replacing the former rings made of brass.
These new steel rings guarantee the high standard of gearshift precision
expected of a sports car, with gear strength and service life increasing
approximately by a factor of 10. The driver himself will feel this
improvement above all when shifting gears quickly, smoothly and crisply even
at high speeds like in motorracing.
Splash oil lubrication and the new external transmission fluid cooling again
confirm how carefully the transmission has been prepared for motorsport
requirements. With this new concept, a pump extracts the hot oil and sends
it through an oil/water heat exchanger integrated in the engine cooling
system. After being cooled down, the transmission fluid is sprayed as
required on to the individual gears, thus being used precisely where
critical temperatures have to beavoided.
Chassis and Brakes
Low, Firm, Dynamic
Through its modified chassis and suspension, the 911 GT3 impressively
confirms Porsche's vast experience in motorsport and marks the utmost limit
of what is currently possible in sports car engineering. The chassis is
designed and built for extremely sporting behaviour, superior handling and a
high standard of driving safety. Apart from the general requirements made of
the front and rear axle, this includes, inter alia
• the centre of gravity lowered by approximately 30 millimetres or 1.18"
(with the suspension kinematics being modifiedaccordingly),
• adjustable anti-roll bars and a suspension system compatible with race
springs for various types of tracks andrequirements,
• a larger range of axle geometry adjustment for the use of sportstyres, and
• the reinforcement of relevant components such as the swivel bearings and
wheel mounts at the front.
Axles with all the qualities required
To reflect the higher standard of performance on the road, the new 911 GT3
comes with even firmer springs, dampers and anti-roll bars. An
outside-thread damper leg on the front axle and height-adjustable spring
plates provide the possibility not just to lower the height of the vehicle,
but also to make the necessary fine adjustments. In the interest of precise
damper piston pin mounting with only a minimum influence on axle kinematics
under spring load with the springs being compressed, the support bearings
come with a single-ball joint resting on a metal and not – as is usually the
case with production cars – on rubber. This support bearing is designed to
provide two assembly positions for the different camber of road and racing
tyres requiring only minoradjustment.
The anti-roll bar on the rear axle is adjustable to four different settings.
And the damper leg featuring a single-sleeve gas pressure damper comes with
an even firmer response in the compression and rebound mode. At the same
time the rear axle has been prepared for the use of racing springs,
featuring an outer thread like on the front axle for installation of a
height-adjustable spring plate. The springs are cylindrical, arranged
concentrically to the steering leg axis, and come with progressive response.
The upper spring plate is made of aluminium and is held firmly inplace.
Different chassis and suspension settings
Allowing different settings and adjustments, the chassis and suspension of
the 911 GT3 enables the driver to re-align his sports car for specific
requirements on the race track. These adjustments strictly for racing and
sports requirements are not allowed on public roads, since they have a very
significant influence on the car's handling andbehaviour.
The new 911 GT3 comes with suspension management carefully matched to the
tyres approved by Porsche for road use. This coordination of the various
components even including tyre pressure is based on elaborate tests.
Whenever the original settings are modified, say, for the use of racing
tyres on the race track, it is absolutely essential to return to the
original setting before driving the car again on public roads with regular
tyres. And it is equally essential to remember that no single chassis and
suspension setting is able as a kind of compromise to cater for all
drivingconditions.
Limited-slip differential on the rear axle
The 911 GT3 comes as standard with an asymmetric-control limited-slip
differential. Since, thanks to its underlying concept with the engine at the
rear and the resulting distribution of weight, the 911 GT3 has all the
qualities required for getting the power of the engine safely on to the road
even on slippery surfaces, limited slip of 40 per cent is quite sufficient
under load conditions. Any higher slip factor would only have a negative
effect on the car's behaviour in bends, without providing any significant
improvement oftraction.
The slip factor under engine power is 60 per cent, this higher figure being
chosen first because engine drag forces are lower than the engine's maximum
torque and second because this configuration serves to stabilise the car
against oversteering under load change in a bend. With this system both
wheels are braked more smoothly and consistently when the driver suddenly
takes his foot off theaccelerator.
New brake system with six-piston callipers
With the 911 GT3 being a genuine performer in terms of acceleration,
flexibility and top speed, the brake system is equally outstanding. Indeed,
the brakes on the new 911 GT3 are a further development of the system
already featured on the previous model. And to take the enhanced standard of
performance into account resulting from the increase in engine power and the
optimised chassis and suspension, the brake discs on the front axle have
been enlarged in diameter by 20 millimetres to 350 millimetres or 13.78".
Measuring 34 millimetres or 1.34" in thickness, the cross-drilled,
inner-vented brake discs come with involute cooling ducts patented by
Porsche. These sickle-shaped ducts inside the discs act like a turbine,
making a significant contribution to the brake disc's cooling behaviour. The
new 911 GT3 comes with far more powerful and efficient six-piston brake
callipers finished in red in old Porsche tradition, versus the four-piston
fixedcallipers on the former model. These callipers enlarge the contact area
between the brake linings and the brake discs by approximately 40 per cent
and improve stopping power to an even higher standard even under the
toughestconditions.
The rear wheels feature four-piston brake callipers also in monobloc design,
together with brake discs measuring 330 millimetres or 13.00 in diameter.
Naturally, these brake discs are also cross-drilled and inner-vented, and
measure 28 millimetres or 1.10" across. The brake discs on the front and
rear axle are single-piece units and are made out of one common casting
together with the brake housing in order to reduce weight to aminimum.
Brake spoilers to reduce brake disc temperature
In determining the dimensions of all parts and components, Porsche's
engineers have given priority not only to the increase in performance, but
also to other conditions and requirements of a particular significance on
the race track. This includes the enhanced brake cooling system featuring
brake air spoilers integrated in the wheel arches. Acting as air guidance
vents, these spoilers direct most of the air coming out of the radiators
through the wheel arches directly to the brake discs and callipers, thus
enhancing the thermal capacity and load resistance of the brake system to an
even higher standard. Together with the new rims providing better heat
extraction, the brake air spoilers reduce temperature loads on the brake
discs on a race lap at competition speed by up to 20 percent.
To reduce the transmission of high brake temperatures to the hydraulic
fluid, the brake calliper pistons are separated thermally by heat-insulting
circonium ceramic inserts also protecting the brake fluid from excessive
heat under extremeconditions.
ABS anti-lock brake system
The only electronic control system fitted in the 911 GT3 is the ABS brake
system with intervention parameters matched to the new balance of the
chassis and suspension. A particular feature of this four-channel system is
even faster and more precise brake control. With ABS acting individually on
all four wheels, it serves in particular to improve the car's stability,
brake response behaviour and, as a result, brake stability in bends. Highly
efficient ABS control systems of this kind are an advantage also in
motorsport which Porsche naturally wishes to offer even the most ambitious
driver of a 911 GT3. However, this new sports model intentionally does
without any other, further-reaching drive control and stabilityprograms.
911 GT3 available for the first time with ceramic brake discs
As an option the new 911 GT3 can be fitted with Porsche Ceramic Composite
Brakes (PCCB). These cross-drilled, inner-vented ceramic discs measuring 350
millimetres or 13.78" in diameter are 50 per cent lighter than metal discs
and reduce unsprung masses by approximately 18 kilos. Operating in
conjunction with brake linings also developed especially for this brake
system, the ceramic brake discs immediately provide and maintain a very high
frictional coefficient during application. Clearly, this avoids any
unpleasant surprises for the driver, for example when he is required to
apply the brakes from high speeds, since brakes initially offering a high
level of stopping power but not built especially for high speeds like
Porsche brakes quickly lose their frictional coefficient under high
temperatures and force the driver to exert extra pressure on the brake
pedal. Porsche's new brake system also offers significant advantages when
applied at low speeds, with emergency application of Porsche Ceramic
Composite Brakes requiring neither high pedal forces nor any kind of
technical assistance in order to build up maximum brake power within
fractions of a second.
Compared with metal brake discs, abrasion is extremely low thanks to the
very hard surface of the ceramic discs. This also means a much longer
service life further enhanced by the anti-corrosion qualities of the
material used: Ceramic brake discs are absolutely immune to salt grain and
liquid salt solutions on theroad.
New wheels and tyres exclusively for the 911 GT3
One of the most important objectives of Porsche's motorsport development
engineers in creating the new model was to ensure maximum traction under all
conditions – which made it essential to give the tyres particular
consideration. In close cooperation with one of the world's leading tyre
manufacturers in terms of tyre technology, they thus created new tyres
especially for the new 911 GT3 offering not only superior everyday driving
qualities, but also exceptional dynamic reserves with even more precise
driving and steering behaviour as well as an extremely high standard of
lateralacceleration.
The relatively soft rubber compound of the tyres serves to provide optimum
grip even under high temperatures. Until further notice, the 911 GT3 will
come exclusively with these tyres for road use. Winter tyres and special
snow chains are however available as an option, as with the 911 Turbo.
Light-alloy wheels larger but lighter
The new tyres run on new rims with the GT3 logo on the wheel hub cover. Rim
width at the front is up from 8 to 8 1/2 inches, with 235/40 ZR 18 tyres.
The rear rims now measure 11 instead of 10 inches in width, running on
295/30 ZR 18 tyres. Despite the larger rim and wheel combinations,
innovative design of the rims reduces the weight of the overall wheel system
by more than 1 kg versus the previous model. And the consistent focus on
lightweight design, the production of the wheels in one single piece, as
well as the flow forming production process also help to ensure excellent
wheel strength and stability combined with lowweight.
A wheel repair kit is housed beneath the carpet in the luggage compartment
for the event of a puncture. Consisting of a can containing repair foam, a
tyre pressure compressor, and an air pressure gauge, this kit has already
proven its qualities most convincingly in the event of minor tyre damage.
After sealing a hole and pumping up the tyre with the kit, the driver can
proceed to the nearest workshop without anyproblems.
Aerodynamics
Excellent Driving Behaviour to the Utmost
The new 911 GT3 lives up in every respect to the sporting impression it
conveys at first sight. Each and every millimetre of the car is designed and
built for maximum performance. This is also applies to the newly designed
front end with its steeper swept angle, the new side-sills and the
dominating rearspoiler.
This aerodynamic refinement is the result of thorough testing in the wind
tunnel as well as the experience gained in 911 GT3 Cup motor racing.
Expressed in figures, the 911 GT3 has a drag coefficient of 0.30 quite
outstanding for a car of this type. And although this figure is exactly the
same as on the previous model, lift forces on the front and rear axle have
been reduced once again mainly thanks to the redesigned front end,
side-sills and rear spoiler. With its 40-millimetre-wide spoiler “lip"
extending all the way round, the new front end significantly reduces the
flow of air beneath the car. The optimum position of the cooling air
openings, in turn, guides most of the air coming out of the radiators at the
side directly to the brake system and not beneath the car, again helping to
significantly reduce front axle lift.
Optimum balance of lift forces
Aerodynamic improvements at the front and rear are carefully harmonised to
provide optimum balance of lift forces on the front and rear axle. The flow
of air around the rear wheels is improved by the aerodynamically optimised
side-sill covers as well as the wheel spoilers upstream of the wheel arches.
In comparison with the former model, the rear wing offers an even higher
standard of aerodynamic efficiency and, with lift forces being further
reduced, serves to minimise air drag at the same time. For motor racing
events on the track, the rear wing may be set to three different positions
varying by 40 or, respectively, 80 in order to individually adjust the
aerodynamic balance of the car to the respective trackconditions.
Like all Porsche 911 models, the underfloor of the new 911 GT3 is covered
from the front axle all the way to the engine by three extra-large plastic
panels in the interest of good streamlining. These floor covers serve at the
same time to cool components running under high strain by vent openings at
all the appropriatepoints.
The result of this aerodynamic balance of front and rear axle loads tailored
to the car's chassis and suspension is a standard of driving qualities and
handling features that makes the new 911 GT3 a top performer even at very
highspeeds.
Equipment
Sports Cockpit with Leather Upholstery
The 911 GT3 is clearly recognisable from outside at very first sight. But
even inside the car, the driver and his passenger will not have the
slightest doubt where they are, with the GT logo standing out clearly on the
door cut-out trim, on the rear carpet, the handbrake lever handle, and in
the rev counter. The standard interior colour is black, all of the
high-quality plastic components being covered by black soft paint and with
the roof lining finished in blackalcantara.
The leather-padded bucket seats made of a special synthetic material
guarantee optimum side support, but also a very high standard of comfort
even on long distances. A further feature is the reduction in weight, the
new seats weighing about 20 kg less than the seats in the 911 Carrera. To
further optimise vehicle weight, the 911 GT3 comes without rear seats again
saving 8 kilos. The three-spoke leather steering wheel offers sporting
qualities in every respect, with adjustment for reach by up to 40
millimetres or 1.6" in order to give the driver his perfect, ergonomic
seating position. The modified dashboard, in turn, now comes with a lockable
glove box as well as a cupholder. The new orientation lights comprise
light-emitting diodes in the door linings, in the courtesy light on the roof
lining, and at the front of the door closing handle to illuminate the
ignition lock and lightswitch.
It almost goes without saying that driver, passenger and side airbags as
well as electric window lifts, an immobiliser complete with transponder,
central locking with remote control and an alarm system are among the
standard features in the 911 GT3. Air conditioning with an activated
charcoal filter is available as a no-cost option and the range of special
equipment serves to fulfill all of the driver's individual wishes, for
example bi-xenon headlights or a telephone preparationkit.
For the really dedicated driver with racing ambitions: 911 GT3 Clubsport
The Clubsport version was specially developed to enable the drvier of the
911 GT3 to participate in motorsport with the homologation required but
without having to elaborately retrofit his car. Features include a roll cage
bolted to the body as well as the absence of side airbags. The cage
interacts with the spring strut supports on the rear axle in order to
stabilise the car, with chassis and suspension forces being fed not only
into the body, but also directly into the roll cage. Under tough motorsport
conditions this means that forces acting on the rear spring struts cause
only minimum deformation of the body. The rear axle geometry, in turn, is
not influenced by these forces and ensures much more precise guidance of the
rear wheels serving again to improve the driving characteristics of the 911
GT3 Clubsport.
Instead of leather, the bucket seats in the Clubsport version come in
flame-resistant cloth upholstery. And apart from the use of red three-point
seat belts the Clubsport model is also fitted with a red six-point seat belt
on the driver's side not homologated for public roads in Germany as well as
a fire extinguisher mounted on a separate support.

 ha scritto nel messaggio
[stracut]
Complimenti per gli oltre 40K di post, sia questo che quello
precedente....mettere un link al posto di copiaincollare tutto è troppo
difficile?

 difficile?
In effetti sono venuti un po' pesantini...sinceramente pensavo avrebbero
occupato meno spazio!
Me spias
Max T.

 difficile?
I siti che contengono le cartelle stampa necessitano di accerediti
particolari per accedervi.
E non è possibile entrarci in modo diretto senza una password che è
personale.
Quindi o si va di copia/incolla o si da la password a tutti o non si dice
nulla....
Buona la prima
Ciao
--
Cristian F. (MI,34,143) PULL  ANNO IV d.C.   dO O   (||||)°(||||)   O Ob
http://communities.msn.it/IlmondodelDrPianale
Io ne ho viste cose che voi naftari non potreste immaginarvi:
TDI da competizione in fiamme al largo dei bastioni di Porta Nuova...
E ho visto i contagiri Jaeger balenare nel buio vicino alle porte degli 8000
E tutti quei momenti andranno perduti nel particolato come lacrime nella
pioggia... E' tempo di fare gasolio.

 Me spias
Ho visto ora la tua replica..ma scusa, da dove li hai copiati?
A me nei siti di 'press' che bazzico mi chiede sempre la password....
possibile che Porsche no?


 possibile che Porsche no?
Basta avere gli indirizzi giusti e non c'è bisogno di nessuna pw... ;-)
Poi ti mando il link!
Ciaooo
Max T.


E qui ti sbagli! :-P
Ciaoooo