2008 PORSCHE 911 GT2 key

· 16 ·· 17 ·
The 911 GT2 |The 911 GT2
being forced into the turbos,
there is less resistance from
the compressors and therefore
less back-pressure in the
exhaust, which means greater
engine performance.
The engine cover, featuring
the GT2 logo, is made from
lightweight glass-fibre reinforced
plastic (GRP). Twin titanium
tailpipes are elegantly incorpor-
ated within the rear apron design.
Warm air is vented from the braking power, with large air
intakes for improved air flow to
the central radiator and front
brakes. The integral air outlet
ahead of the front lid makes a
major contribution to front-enddownforce. The airstream from the
central radiator is channelled up
over the car, forcing the front end
downwards, thereby enhancing
balance and steering response.
The importance of air in the per-
formance of the 911 GT2 is also
apparent from the large intake
openings in the rear side panels
which supply the intercooler units.The most impressive view is also
the one that others will see most
of all: the rear. The fixed rear wing
with integral lip spoiler ensures
optimum stability at speed.
As the car accelerates and you’re
pressed into your seat, air is
forced through the intake openings
on the rear wing uprights and into
the engine turbocharging system.
This ‘ram air’ effect has a key role
to play in the exceptional efficiency
of the engine. Since air is already Power. Torque. Acceleration. All in
plentiful supply. Nothing else can
match that energy – except the
car’s design. A single glance is all
it takes to realise that fact.
The front end is aerodynamically
adapted for the high thermal
load of the engine and increased
Aesthetically. Aerodynamically. Resistance is futile.
Designing the 911 GT2.engine compartment via cooling
slits at the rear.
The combined effect of all these
aerodynamic modifications is a
drag coefficient of just 0.32 as
well as positive front and rear
downforce. Behind the wheel,
that means better grip, better
directional stability and excep-
tional handling characteristics.
Technically and visually, the
result is the same: a breathtaking
driving machine.

· 29 · · 28 ·
The 911 GT2 |Drive
turbine has a lower mass, it
responds more quickly to increas-
ing pressure, spinning up easily
to its optimum speed. The key
disadvantage of using a smaller
turbo is that the back-pressure
generated at higher engine speeds
causes a significant reduction
in performance. Resistance is
caused by the smaller cross-
sectional area through which
the exhaust is required to flow.
On a conventional turbocharger,
the exhaust flow drives a turbine
that is connected to a compressor
on the intake side. By compressing
the incoming air, the amount
of oxygen in a given volume is
increased. Since compression also causes an increase in
temperature, the air must be
cooled in a device known as an
‘intercooler’. With more oxygen
present in each cylinder charge,
more fuel can be burnt, yielding
greater energy. Since higherexhaust pressures generate
greater loads on the intake side,
the intake pressure must be
carefully controlled in order to
protect the engine. This ‘boost
pressure’ is limited using ‘waste-
gate’ valves that bypass excess
pressure around the turbine.
Another important factor in
the system is the size of the
turbocharger. Since a smaller Porsche has a long and celebrated
tradition of using turbocharged
power on both road and track.
On the 911 GT2, we’ve
enhanced
this technology with Variable Turbine
Geometry (VTG).Larger turbo units, which create
lower back-pressure at higher rpm,
take considerably longer to spin
up under power due to the large
cross-sectional area and relative
inertia of the heavier turbine.
Generally, this type of turbo will
only be effective in the medium
rpm range. This phenomenon,
known as ‘turbo lag’, means there
is virtually no turbocharging
effect at lower engine speeds.
Turbocharger with Variable Turbine Geometry (VTG)
Breathe easy – when holding your breath.
Variable Turbine Geometry (VTG).

· 33 · · 32 ·The 911 GT2 |
Drive
Unfortunately, compression not
only increases air volume, it also
increases air temperature and this
has a negative effect on ignition.
Our new expansion manifold simply
turns that principle around. The
internal geometry is radically
different from that on a resonance
intake system. Key modifications
include a longer distributor pipe,
with a smaller diameter, and
shorter intake pipes.Expansion intake manifold.
More power than a 911 Turbo -–
from the same engine? Not easy.
But feasible, which is why it
required yet another spectacular
innovation from Porsche.
The 911 GT2 has an innovative
expansion intake system with a
unique working principle which
overturns the methods previously
used. Our ‘expansion’ intake
mani-
fold is a radical new
developmentthat is the polar opposite of
the resonance principle used
on conventional turbocharged
engines.
A resonance manifold increases
engine output by forcing add-
itional air into the combustion
chambers. To do this, the mani-
fold is designed in such a way
that the air – which vibrates
due to the action of the valves –
is in a compression phase as it
passes through the inlet ports.As a result, the air is in the
expansion phase as it enters the
combustion chambers. Since
expansion always cools, the
air/fuel temperature is lower and
ignition is significantly improved –
thereby increasing performance.
Of course, the amount of air
that enters the engine under
expansion is less than it would
be under compression. To
compensate for this, we’ve simply
increased the boost pressurefrom the turbochargers by
approximately 0.2 bar. The result-
ing increase in temperature –
again through compression – is
immediately offset by the uprated
intercoolers.
Instead of hot compressed
air entering the combustion
chambers, we now have cooler
air generating more power and
torque. As a consequence,
there is a major improvement in
engine efficiency and thereforelower fuel consumption even under
heavy loads and at high rpm.
A simple solution, but then that’s
often the way when you take
a new approach to old ideas.
Expansion intake manifold

· 37 · · 36 ·
The 911 GT2 |Drive
benefits, such as optimum econ-
omy, emissions and performance
in all driving scenarios.
One of the most important tasks
performed by the engine manage-
ment system is cylinder-specific
knock control. By preventing pre-
ignition at high engine speeds
and loads, this function can avert
costly damage to the pistons and
cylinders. Since temperatures
tend to vary across the engine,
each cylinder is monitoredseparately. If a risk is detected,
the individual ignition timing is
adjusted.
The on-board diagnostics system,
designed to European standard,
quickly detects any faults in the
exhaust and fuel system and
displays them during driving
via the car’s instruments. The
benefits include active prevention
of harmful emissions as well
as consistent rates of fuel con-
sumption.Input data Used to regulate /control
Digital engine electronics
(ME7.8.1 control unit)
Engine load
Pressure upstream from throttle
Throttle-valve angle
Engine speed (from crankshaft)
Inlet camshaft phase angle
Throttle-pedal position
Oxygen sensor signals
Knock sensor signals
Ignition
Fuel injection
Throttle valve
Heating elements in oxygen sensors
Fuel pump
Fuel-tank venting
CAN interface to transmissionMoment interface to Porsche
Stability Management (PSM)
VarioCam Plus
– camshaft phase angle
– valve lift control
Electronic controller for
Variable Turbine Geometry (VTG)
Recirculation valve
Secondary air injection
Engine-bay fan
Starter
On-board diagnostics
Air-conditioning compressor
Interface to instrument cluster
Radiator fans (front control unit via CAN)
Vehicle speed
Air-conditioning settings
Engine immobiliser status
Clutch pedal switch
Ambient air pressure
Temperatures
– coolant
– air upstream from throttle
– engine oil
– air in engine compartment
– ambient air
Exhaust-gas temperature
Engine management system.
The Motronic ME7.8.1 engine
management system facilitates
optimum performance at all
times. This high-precision ECU
controls all engine-related func-
tions and assemblies (see
dia-
gram), such as Variable Turbine
Geometry, VarioCam Plus and
the electronic throttle, one of the
key prerequisites for the standard
Porsche Stability Management
(PSM). This produces various

· 53 · · 52 ·
The 911 GT2 |Chassis
The steering system is extremely
direct and provides detailed
feedback from the road. This
high level of precision is very
advantageous in both racing and
normal road use. Thanks to the
precise front-axle kinematics andthe variable steering ratio, the
car responds to every movement
of the wheel.
An important feature of the
steering system is the variable
ratio gearing. Around the straight-ahead position, the ratio
is less direct, enabling smoother
manoeuvres, such as during
motorway driving. There is less
risk of excessive steering inter-
vention destabilising the car at
high speed. Naturally, the systemprovides excellent feedback as
well as the usual agility. As the
wheel is turned harder, the ratio
becomes more
direct and the
steering more responsive. This
variability is
particularly beneficial
in low-speed hairpin bends. The
energy-absorbing steering column
is a key safety feature since, in
the event of a front-end impact, it
enables a deformation path of
100 mm.The intermediate steering shaft is
made from aluminium, while the
protective tube and steering lock
housing are die-cast magnesium.
The standard three-spoke GT2
steering wheel features manual
height and reach adjustment.
Used in conjunction with the seat
adjustment options, it enables
every driver to find the ideal seat-
ing position.
Maximum precision, however powerful the performance.
Steering.

· 59 · · 58 ·
The 911 GT2 |Safety
The 911 GT2 is equipped as
standard with the Porsche
Ceramic Composite Brake (PCCB)
that has already demonstrated
its performance credentials on
the racetrack, for example, in the
vehicles of the Porsche Mobil 1
Supercup.only much harder than metal, it
is also more resistant to heat.
Even at high temperatures, the
thermal resistance of the PCCB
disc ensures exemplary dimen-
sional stability. The ceramic
material is totally resistant to
The large disc diameter (380 mm
front and 350 mm rear) adds sig-
nificantly to brake performance.
The ceramic discs are made from
a specially treated carbon-fibre
compound that is silicated in a
high-vacuum process at 1,700 ºC.
The material thus produced is notcorrosion and offers excellent
acoustic damping properties.
The pads are mounted in six-piston
monobloc aluminium fixed calipers
at the front, with four-piston units
at the rear. The resulting brake
forces are not only extremely
high, they are also exceptionally
consistent. The pedal response
is fast and precise with only
moderate input required.
PCCB enables shorter braking
distances in even the toughest
road and race conditions. Excel-
lent fade resistance ensures
greater balance when slowing
from racetrack speeds.
The key advantage of PCCB is
the total weight saving of approxi-
mately 50 % over comparable
metal discs. The mounting bells
on both front discs are made
from weight-saving aluminium. As
well as enhancing performance
and fuel economy, there is a major
reduction in both the unsprung
and rotating masses. This, of
course, improves comfort and
road-holding on uneven road
surfaces as well as general
handling and agility.
Please note that circuit racing,
trackday use and other forms of
performance driving can signifi-
cantly reduce the service life of
even the most durable pads and
discs. As with conventional high-
performance braking systems,
we recommend that all brake
components be professionally
inspected and replaced where
necessary after every track event.
Porsche Ceramic Composite Brake (PCCB)
When it comes to brake technology, we demand nothing but the best.
Porsche Ceramic Composite Brake (PCCB).

· 69 · · 68 ·
The 911 GT2 |Comfort
the rev counter. A centrally placed,
clearly visible arrow indicates the
latest time to change gear.
On-board computer.
The integral on-board computer
gives information on boost pres-
sure, average fuel consumption,
speed, remaining distance andexterior temperature. It can also
be used to view data from the
standard Tyre Pressure Monitoring
(TPM) as well as the timing system
featured in the optional Chrono
Package Plus (see page 75).
The computer is operated using
a control stalk on the steering col-
umn, with information displayed in
the instrument cluster.
Instruments.
The sporting credentials of the
911 GT2 refer not only to engine
and chassis, it also boasts a sporty
interior designed around the driver.A car like the 911 GT2 requires
an ergonomically efficient driving
environment with unhindered
access to all key information.
Clearly visible at the centre of
the cluster of five instruments is a large rev counter with GT2
logo and titanium-coloured dial.
The needles and markings in the
instrument cluster are yellow.
For optimum acceleration, you
can view the upshift display in Other standard features include
automatic air conditioning with
active carbon filter.
We’ve demanded your respect. Now have ours.
Interior.

· 75 · · 74 ·
The 911 GT2 |Comfort
‘Welcome Home’ lighting.
This standard lighting function
provides comfort and safety at the
push of a button. The low-beam
headlights are automatically
illuminated when the car is locked
or unlocked using the key remote.
The lights remain illuminated for
a predefined period, lighting your
way to or from the car. This delay
is user-adjustable via Porsche
Communication Management
(PCM) on vehicles with the optional
Sport Chrono Package Plus.
ParkAssist.
This optional parking aid is auto-
matically enabled whenever you
select reverse gear. Move too
close to a stationary object and a
warning signal is emitted. Continue
to reverse and the tone increases
in frequency. The distance is
measured by ultrasonic sensors
which are neatly concealed in the
rear bumper.
Cruise control.
This convenient option has an
effective range of 30 – 240 km / h
(19 – 149 mph). The system is
operated using a switch in a
separate control stalk on the
steering column and can even
be used in first gear.
HomeLink®
(garage door opener).
This optional garage door opener
is freely programmable and inte-
grated within the cockpit. It offers
remote control for up to three
garage, gate, home lighting and/or
alarm systems and is compatiblewith almost all garage and exterior-
door systems.
Automatically dimming interior
and exterior mirrors.
An auto-dimming function is
available as an option for the
911 GT2 for interior and exterior
mirrors. The package also includes
an integrated rain sensor for the
front wiper system.
Luggage compartment.
The volume of the luggage
compartment in the 911 GT2 is
105 litres. The entire compartment
is lined with high-quality, scratch-
resistant materials. The bulkhead
panelling conceals the amplifier
of the optional BOSE
®Surround
Sound System and the DVD drive
for the optional navigation module.
The additional 205-litre rear load-
space inside the car is easily
accessible thanks to the folding
sport bucket seats.
Anti-theft protection.
The 911 GT2 has an engine
immobiliser with in-key transpon-
der as well as a powerful alarm
system featuring contact-sensitive
exterior protection and radar-
based interior surveillance as stan-
dard. The alarm system is
activated and deactivated by a
remote control function in the
ignition key.
Vehicle tracking system.
The 911 GT2 can also be equipped
with an optional factory-fitted
preparation enabling future
installation of a vehicle trackingsystem obtainable from Porsche
Tequipment. This system allows
a stolen vehicle to be traced
throughout most of Europe, and
requires the installation of a
special wiring loom and a high-
capacity battery.
Chrono Package Plus.
The optional Chrono Package Plus
combines a dash-mounted
analogue/digital timer with a range
of useful functions. Lap or journey
times can be viewed, stored and
analysed using the performance
display in PCM. The information
available includes time elapsed
and distance travelled on the cur-
rent lap, as well as the number
oflaps completed and their
respec-
tive times. You can also view the
current fastest lap and remaining
range till empty. Driving times can
be recorded for any stretch of
road, and benchmark times can be
defined. Other useful
features
include a personal
memory func-
tion, controlled via PCM, which
stores personal preferences for a
range of systems, including lights,
wipers, door locks and air condi-
tioning.
Luggage compartmentChrono timer