2008 PORSCHE 911 GT2 radiator

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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.

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The 911 GT2 |Drive
VarioCam Plus
Engine cooling.
The engine of the 911 GT2 features
cross-flow water cooling with fully
integrated coolant management.
This technology ensures a consis-
tent flow of coolant to each of
the engine’s cylinders. Waste
heat from the oil is transferred to
the coolant via two oil/water heat
exchangers. The coolant is routed
through twin radiator modules
ahead of the front wheels and a
centrally placed unit in the nose.
VarioCam Plus.
VarioCam Plus is a variable valve
timing system on the inlet side
which also features two-stage valve
lift. The benefits it provides include
greater power and torque at all
engine speeds, as well as excellent
running characteristics, better fuel
economy and fewer emissions.
Essentially, VarioCam Plus makes
two engines out of one. The first is
geared for normal road driving, thesecond for high-performance use.
The system switches seamlessly
between the two as the driver
inputs change. All operations
are controlled by the engine
management system. The results:
emphatic acceleration and
smoother running.
The two-stage lift mechanism
on each inlet valve consists of an
electro-hydraulically switchable
tappet. Each of the 12 tappets con-
sists of two concentric parts – anouter ring and a central shaft –
which can be locked together by
means of a pin. The system can
then vary the valve lift by using
two large profile cams on the outer
ring or a smaller cam lobe on the
central shaft. The timing of each
valve is steplessly controlled by
means of an electro-hydraulic
rotary vane adjuster at the head
of the corresponding camshaft.
To improve responsiveness during
warm-up in cold weather, VarioCam
Plus will select the higher valve
lift setting and retard valve timing.
At medium revs and low engine
loads, the lower valve lift setting
is activated and timing advanced in
order to reduce fuel consumption
and emissions. The economy of
the engine is particularly enhanced
at lower engine speeds. For maxi-
mum power and torque, the higher
lift setting is selected and the tim-
ing of the valves is advanced.This results in copious torque
and exceptional fuel economy,
particularly in comparison with
much larger engines offering
similar power output.

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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

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The 911 GT2 |Drive
1. Bi-Xenon headlights
2. Radiator module (left)
3. Radiator module (centre)
4. Radiator module (right)
5. Coolant pipe9. Intercoolers
10. Pressure pipe
11. Throttle valve
(electronically actuated)
12. Expansion intake manifold 6. Coolant expansion tank
7. Air filter
8. Exhaust-gas turbocharger
with Variable Turbine
Geometry (VTG)17. Generator
18. PASM damper
19. PCCB brake
20. Tandem brake booster
21. 6-speed manual gearbox
22. Sport bucket seat
13. Main silencer (titanium)
14. Tailpipe (titanium)
15. Oil filter
16. Engine oil reservoir
(dry-sump lubrication)