2010 PORSCHE CAYENNE tire pressure

consistently within a specific
temperature range. The engines
in the new Cayenne models are
therefore designed for optimum
cooling.
The V8 engines have an enhanced
coolant management system
offering effective temperature
control throughout the engine.
While 20% of coolant flows longi­
tudinally through the crankcase,
the remaining 80% serves the
cylinder heads using the proven
cross ­flow principle (from hot to
cold).
On all Cayenne models, the piston
heads are cooled using oil ­spray
jets integrated within the main
lubrication system. In addition,
thermal management ensures
that the optimum operating tem ­
perature for the engines is
reached more quickly. This keeps emissions and fuel consumption
low, even when starting from cold.
The entire cooling system is
designed for prolonged heav y
­

dut y use, e.g. of f ­road driving
or heav y towing and carrying
applications.
Lubrication.
The V8 engines use dry ­sump
lubrication to ensure a consistent
supply of oil in all load conditions,
especially in of f ­road terrain.
The oil reservoir is located inside
the engine. This saves on space
and reduces weight.
Oil is circulated around the V8
engines using a demand ­driven
pump. This has been designed for the toughest driving scenarios
on and off road, including per­
formance driving and extreme
gradients.
The V6 engine in the Cayenne has
a wet ­sump lubrication system.
Ensuring a reliable supply of oil,
no mat ter how challenging the
driving conditions.
Direct fuel injection on the
diesel engine (common-rail
injection system).
On the Cayenne Diesel, direct
fuel injection comes courtesy of
a common ­rail injection system.
The injection pressure of up
to 1,800 bar ensures optimum
distribution of the air/fuel mixture
– for greater performance. The
piezoelectric injection valves
provide flexible injection rate

adjustment, using exactly metered
quantities of fuel, with multiple
injections for each power stroke
to deliver smooth combustion.
Cooling systems.
A high ­performance engine can
only maintain its maximum
capabilit y over a long service life
if all components are operating
Direct fuel injection (DFI).
DFI injects fuel directly into the
combustion chamber at up to

120 bar with millisecond precision
using electromagnetic injectors.
The injector position and spray
geometry have been carefully
designed to improve output,
torque, fuel economy and emis ­
sions. The swirling of the fuel as
it enters each chamber increases
the mixing of air and fuel, thereby
enhancing combustion. By form ­
ing the air/fuel mixture directly
in the combustion chamber, DFI
contributes to engine cooling.
As a result, it was possible to in ­
crease the compression ratio and
therefore power and efficiency.

Compression with precision.
Essential for getting right to the point.
38 · Drive systems and chassis | Engine technology

response, even at low revs and
road speeds. This is particularly
useful when driving in urban
traf fic. The supercharger has a
low­temperature water cooling
system for cooling the charge air.
Variable Turbine Geometry in
the new Cayenne Diesel.
The turbocharger in the new
Cayenne Diesel features Variable
Turbine Geometry (V TG). The
gas ­flow from the engine is
channelled onto the turbines via
electronically adjustable guide
vanes. By changing the vane
angle, the system can replicate
the geometry in all t ypes of
turbo, large or small, and thus
achieve the optimum gas ­flow characteristics. As a result, even
at low engine rpm, the turbine
speed is maximised. For a sig
­
nificant increase in boost pres ­
sure, excellent cylinder charging
plus greater power and torque.
Electronic engine management.
Cultured performance in all
driving scenarios requires com ­
prehensive engine control. The
electronic engine management
system does this by continually
monitoring the relevant input data
from a variet y of sophisticated
sensors. This data is then com ­
pared with a corresponding set of
reference values. Based on this
information, a range of key engine
functions, e.g. ignition and in­
jection timings as well as injection
quantities, are seamlessly and
automatically adjusted. Other
major functions include automatic
compensation for changes in fuel
qualit y and control of the variable ­
tract intake manifold. On the
new Cayenne Turbo, the engine management system also regu ­
lates the turbo boost pressure.
The results:
optimum fuel eco
n ­
omy and lower CO
2 emissions as
well as greater power and torque
at all times.
Exhaust system.
The light weight exhaust systems
in the new Cayenne models are
made from special, long ­life stain ­
less steel. The key features of
the catalysts are high ef ficiency,
faster warm ­up and a long service
life. The sports exhaust system
1)
available as an option on the
new Cayenne and new Cayenne S
provides an even more distinctive
sound. The package also includes
a specially designed set of t win
dual ­tube tailpipes. All exhaust
systems, standard and sports,
comply with the strict EU5 emis ­
sions legislation.
2)
Turbocharging system in the
new Cayenne Turbo.
In the new Cayenne Turbo, the
engine is assisted by t win turbo ­
charger units arranged in parallel
– one for each bank of cylinders.
Incoming air is passed through
a filter and compressed by the
turbine units. Its temperature is
then reduced in the t win inter­
cooler system, which improves
cylinder charging and limits
thermal loads on the engine.
Supercharging system in the
new Cayenne S Hybrid.
The engine in the new Cayenne S
Hybrid is equipped with a
supercharger. For a more direct
Air intake system.
The Cayenne models are all
equipped with a resonance air
intake system. This technology
uses the pressure waves
generated by the inlet valves
to ‘force’ air into the engine.
The ef fect is enhanced in the new
Cayenne and new Cayenne S by
a t wo ­stage intake manifold. This
variable geometry combines all
the benefits of a long intake tube
(higher torque at low rpm) with
those of a shorter length (more
power at higher rpm).
The result: highly impressive
torque ratings across the entire
engine speed range.
1 ) Introduction planned for 09/2010. For new Cayenne only in conjunction with Tiptronic S.2) The data presented here was recorded using the Euro 5 test procedure (715/2007/ EC and 692/2008/ EC) and the NEDC (New European Driving
Cycle). The respective figures were not recorded on individual vehicles and do not constitute part of the of fer. This data is provided solely
for the purposes of comparison bet ween the respective models. Provisional data only. Of ficial data unavailable at the time of publication.
For more information on individual models and final data, please contact your Porsche Centre. Tailpipes on the Cayenne, Cayenne Diesel,
Cayenne S and Cayenne S Hybrid
Tailpipes on the Cayenne Turbo
Drive systems and chassis | Engine technology · 41