2010 PORSCHE CAYENNE fuel pump

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

An electr ic pump is used to
m a i ntain the r equired p ressu re
of the t ransmis sion fluid , e.g.
to t ransmit high levels of torque
at lower engine speeds.
The s tanda rd three­spoke steering
wheel in conjunction with
T i p t r o nic S h as t wo e rgonom ic
switches for manual gear
c h a n g es. One p ress forwa rd with
the thumb and Tiptronic S shif ts
up. One pull backwa rds with
the in dex finger and Tiptronic S
shif ts down. Either the right or
l eft ­hand switch can be used.
tackling as
cents and towing loads
in off ­road ter rain. Top speed
is r eached in 6th gea r. The t wo
upper gea rs a re used to lower
the r evs at high speed , the reby
enhancing fuel economy and
occupa nt comfo rt. On the motor ­
way in pa rticular , driving at low revs will s ignifica ntly reduce the
noise level in side the veh icle.
In automatic mode, the driver
can influence gea rshifts on the
Tiptron ic S using the throt t le and
br ak es alone.
Tiptronic S auto ­
mat ically adapts the gea rshif t
points for performance driving –
equally , if a mo re d efen sive driv ­
ing s tyle is det ected , the sy stem
se lects a gea rshift poi nt that
o f f e rs maximum fuel economy.
Un der heav y b raking , Tiptron ic S
shifts down to maxi mise engine
br aking. Natu
rally , you can also change
gear u sing the gear se lector lever
on the ce ntre cons ole.
Standard on the new Cayenne
Diesel, new Cayenne S, new
Cayenne S Hybrid and new
Cayenne Turbo. Optional for
the new Cayenne.
Eight-speed Tiptronic S.
The out standing feature of the
new eight ­speed Tiptron ic S is a
pa rticularly wi de r atio sp read.
Fi rs t gear is designed for optimum
acceleration when pulling away
and g rea ter performance when
Six-speed manual gearbox.
The six ­speed manual gearbox
on the new Cayenne has been
specifically adapted for the
demands of high ­performance
use. The gear lever throw is short
and precise, and each of the
six ratios has been selected for
optimum progression through
the gears. As the centre console
rises to meet the dashboard, the
gear lever is close to hand –
for an even more engaging drive.
The standard upshif t display in
the instrument cluster helps
to reduce fuel consumption still
further.
Eight ­speed Tiptronic S is also
available as an option on the
Cayenne in conjunction with the
auto start /stop function.
Standard on the new Cayenne.
Precision control.
Whatever your choice of terrain.
Transmission.
Tiptronic S gear selector
42 · Drive systems and chassis | Transmission Drive systems and chassis | Transmission · 43

high­mounted upper arms are now
in aluminium. This axle design
ensures accurate wheel location,
greater agilit y and minimal inter ­
ference on uneven surfaces.
The subframe is secured on large
rubber mountings that reduce
road noise to a minimum. It is
also specially constructed to
increase stabilit y. For enhanced comfort and even greater active
and passive safet y. In the event
of an impact, the subframe
deforms in a predefined manner.

Rear axle.
The rear axle features multi
­link
suspension. Ideal for performance
road and track use, it also copes
well with the extremely high
towing and carrying loads that
are possible with each Cayenne.
The suspension struts are angled
to allow longer suspension travel
and create a deeper and wider
cargo area. As well as providing
additional space, the car is also
easier to load. The rear axle design minimises
dive and squat under acceleration
and braking. It also improves mid
­
corner stabilit y and compensates
for sudden load transfer. In short:
it enables a more relaxed way
of driving. Examples of intelligent
light weight construction on the
rear axle include hollow drive
shafts.
Steering.
The steering system has been
completed revised and adapted
for a sportier driving st yle.
Around the straight ­ahead pos­
ition, in particular, the ratio is
now more direct. With the variable
steering ratio and special valve
set tings on the power ­steering
system, optimum manoeuvrabilit y
is ensured. The turning circle of
the new Cayenne models is just
11.9 metres.
The steering column itself
consists of multiple collapsing
sections linked by t wo universal
joints and a special deformation
element provides additional safet y
in the event of a front impact. Electro
­hydraulic power steering
is used for the first time on the
Cayenne S Hybrid. The demand ­
driven pump only provides
assistance to the steering as
and when required, thereby

contributing to overall efficiency.
Servotronic.
Servotronic is a speed ­sensitive
power steering system.
At higher speeds, the steering
becomes firmer, inputs are more
precise and driver comfort is
enhanced. At lower speeds, it
enables easy manoeuvrability
and parking.
Standard on the new Cayenne S
Hybrid. Optional for the new
Cayenne, new Cayenne Diesel,
new Cayenne S and new
Cayenne Turbo.
Front axle.
The chassis on the new Cayenne
models of fers a direct response –
for a more rewarding driving
experience.
The wishbones on the subf rame­
mounted front suspension with
Weight reduction.
The axle concept on the new
Cayenne models features con­
sistent light weight construction
thanks to the use of new mater­
ials. The results: enhanced driving
dynamics, lower fuel consumption
and optimum occupant comfort.
Shedding weight.
Adding agility, economy and comfort.
Drive systems and chassis | Chassis · 55