2010 PORSCHE CAYENNE engine

sensors are used to measure a
range of values, including the
rotational speed of all four wheels,
the lateral and longitudinal
acceleration of the car, and
the current steering angle.
If, for example, the rear wheels
threaten to lose traction under
acceleration, a greater proportion
of drive torque is automatically
transmit ted to the front axle by a more positive engagement of
the multi
­plate clutch. In addition,
ASR minimises wheel spin. During
cornering, the required level of
engine torque is distributed to the
front wheels to ensure excellent
lateral stabilit y.
In conjunction with advanced
Porsche Stabilit y Management
(PSM, p. 66), PTM ensures the
perfect distribution of drive
torque for optimum traction in all road scenarios, whether on
long straights, through tight cor
­
ners or on surfaces with dif ferent
friction coef ficients. If one of the
wheels is about to lose traction,
PTM uses the ABD function to
apply the corresponding brake.
As a result, more drive is auto ­
matically transferred to the op­
posite wheel. If both wheels on
one axle are in danger of slipping,
ASR immediately intervenes and
modifies engine output to main ­tain drive. As well as enhancing
traction and active safet y,

Porsche Traction Management
(PTM) of fers exceptional handling
and driving dynamics.
Standard on the new Cayenne,
new Cayenne S and new
Cayenne Turbo.
Torque is distributed bet ween the
front and rear axles by means of
the electronically variable multi
­
plate clutch. For the toughest
off ­road terrain, the differential
can be locked using the PTM
control on the centre console.
With the aid of on ­board sensors,
the status of the car is continu ­
ously monitored and the front /
rear split is adjusted to match
changing driving conditions. The
Porsche Traction Management
(PTM) on the new Cayenne,
Cayenne S and Cayenne Turbo.
Porsche Traction Management
(PTM) is an active all ­wheel drive
system with an electronically
variable, map ­controlled multi ­
plate clutch, automatic brake
dif ferential (ABD) and anti ­slip
regulation (ASR).
Intelligent, discreet, responsive.
The ideal travelling companion.
All ­wheel drive on the Cayenne, Cayenne S and Cayenne Turbo
Drive systems and chassis | Transmission · 45

dynamics. Specifically, this means
that when entering a corner at
high speed, moderate brake pres­
sure is applied to the inside rear
wheel. This supports the steering
motion of the car, thereby im­
proving its cornering dynamics.
Standard on the new Cayenne
Diesel and new Cayenne S
Hybrid.
Porsche Hill Control (PHC).
A standard feature on all new
Cayenne models, Porsche Hill
Control (PHC) provides downhill
assistance by maintaining a constant rate of speed on extreme
downhill gradients. It is activated via a switch on the centre console.
The speed can be set to bet ween
3 and 30 km/ h (2 and 19 mph).
transmits the torque to the axle
offering the highest level of trac
­
tion. The ASR and ABD systems
work in the same way as in
the PTM on the new Cayenne,
Cayenne S and Cayenne Turbo.
On the Cayenne Diesel and
Cayenne S Hybrid, PTM also
enables variable distribution
of engine torque to the rear
wheels, thereby enhancing
steering precision and driving
Porsche Traction Management
(PTM) on the new Cayenne
Diesel and Cayenne S Hybrid.
The new Cayenne Diesel and
new Cayenne S Hybrid feature a

permanent all ­wheel drive system
with self ­locking centre differen ­
tial. This provides a standard
torque split of 60% to the rear
and 40% to the front. If one of the
wheels is about to lose grip, the
self­locking centre dif ferential
Drive systems and chassis | Transmission · 47

Available on the Cayenne,
Cayenne Diesel, Cayenne S

and Cayenne Turbo, this function
readies the car for of f ­road use
or reverts the set ting to normal
road driving.
In Of f ­road Mode 1, for example,
the maps for all relevant
systems, e.g. ABS, are adapted
to provide optimum traction. In
addition, Porsche Hill Control

is activated and High Level I is
selected on vehicles featuring air
suspension with PASM. If that ’s
not enough, the air suspension
can be raised further to High
Level II to increase the approach/
departure angle and wading depth.
Push the of f ­road control forward
again on the Cayenne, Cayenne S
and Cayenne Turbo to activate
Off ­road Mode 2 – for even great ­
er traction on dif ficult terrain,
the multi ­plate clutch can be fully
locked.
The electronically variable rear
differential on the optional
Porsche Torque Vectoring Plus
(PT V Plus) is integrated within
the all ­wheel drive system. This
automatically ensures the opti ­mum distribution of drive torque
on particularly uneven surfaces.
If one of the rear wheels begins
to slip, the rear dif ferential varies
the amount of torque transmit ted
through each drive shaf t, thereby
restoring traction. In Of f
­road
Mode 3, the rear dif ferential can
be manually locked using the main
of f ­road control. Then both rear
wheels receive the same amount
of torque, regardless of surface
conditions. The optional PDCC
(p. 53) enables greater wheel
articulation in all three modes,
improving traction still further.
For effective prevention of dam ­
age to the underside of the car,
all new Cayenne models can be
equipped with optional of f ­road
underbody protection comprising
rock rails with integrated skid plates, a reinforced engine
­bay
guard, additional protection
for fuel tank and rear axle, and
a second towing lug.
Operating concept.
With the help of Porsche Traction
Management (PTM), the Cayenne
can cope with even the most
demanding of f ­road scenarios.
Simply move the main of f ­road
control on the centre console
forward or backward to select
one of up to three off ­road
modes (depending on the model).
Steep ascents leading to snow
­
covered mountain lodges, boggy
ground or muddy, loose surfaces
– all situations that the Cayenne
handles superbly with intelligent
all ­wheel drive. The drive systems
featured on the new Cayenne
models deliver exceptional torque.
For plent y of power on tap. On
any terrain.
From urban jungle to the windy wilds.
The new Cayenne: perfectly at home on any terrain.
Off-road capability.
Drive systems and chassis | Of f ­road capabilit y · 49
Main of f ­road control

Making headway without getting in a spin.
An approach we thoroughly support.
Chassis.
In of f­road terrain, PT V Plus
reduces wheel spin on the rear
wheels – even when towing heav y
trailer loads. The electronically
controlled rear dif ferential can
be fully locked using the of f ­road
control on the centre console.
Optional for the new Cayenne,
new Cayenne S and new
Cayenne Turbo.
Porsche Active Suspension
Management (PASM).
PASM is an electronic damping
control system. It of fers con­
tinuous adjustment of individual
damping forces based on current
road conditions and driving st yle.
During performance driving or
heav y of f ­road use, there is an
increased tendency for the body
to sway. PASM prevents this from
happening, thereby improving
stabilit y and occupant comfort. PASM has three setup modes:
‘Comfort ’, ‘Normal’ and ‘Sport ’.
Whichever one you select, the
system uses a series of sensors
to monitor the movement of the
body. It also gathers data on
lateral acceleration, steering
angle, brake pressure and engine
torque and modifies the damping
force on each individual wheel

in accordance with the selected
mode. PASM remains active at all times.
It automatically adapts to the
prevailing driving conditions,

enabling greater car control and
improving comfort and safet y.
Optional for the new Cayenne,
new Cayenne Diesel, new
Cayenne S and new Cayenne S
Hybrid. Standard on the new
Cayenne Turbo: air suspension
with PASM.
This transfers drive torque to the
outside rear wheel which supports
the steering motion of the car,
thereby improving its cornering
dynamics.
At slow and medium speeds, PT V
Plus considerably enhances agilit y
and steering precision. At high
speeds, during fast cornering and
under wheel spin, the mechanical
limited ­slip rear differential
ensures additional stabilit y. Also
on variable ­grip surfaces, in the
wet and on snow, PT V Plus –
combined with Porsche Traction
Management (PTM) and Porsche
Stabilit y Management (PSM) –
provides a major contribution to
active safety.
Porsche Torque Vectoring Plus
(PTV Plus).
A new system for enhancing
driving dynamics and stabilit y,
PT V Plus offers variable distribu ­
tion of engine torque to the rear
wheels and mechanical limited ­
slip rear dif ferential. Depending
on the steering angle, steering
speed, throt tle pedal position,
yaw velocit y and vehicle speed,
PT V Plus optimises steering re ­
sponse and precision by applying
brake pressure to the left or right
rear wheel, as required.
Specifically, this means that when
entering a corner at high speed,
moderate brake pressure is
applied to the inside rear wheel.
Porsche Active Suspension Management (PASM)
50 · Drive systems and chassis | ChassisDrive systems and chassis | Chassis · 51

Porsche Ceramic Composite Brake (PCCB)
To do this, the engine manage­
ment system adjusts the gener­
ator current depending on the
brake pedal position, recovers
part of the kinetic energy and
stores it in the bat tery. When

the pressure on the brake pedal
exceeds a certain threshold, the
brakes are applied.
Porsche Ceramic Composite
Brake (PCCB).
Available as an option on all new
Cayenne models, the Porsche
Ceramic Composite Brake (PCCB)
has already proven its abilit y to
cope with the harshest require ­
ments of the racetrack. It is
available in conjunction with
20 ­inch wheels or larger for the
Cayenne Turbo and with 19 ­inch
wheels or larger for all other
Cayenne models.
The cross ­drilled discs are
generously proportioned: on
the Cayenne Turbo they have
a diameter of 410 mm at the

front and 370 mm at the rear,
while on all other models they
measure 390 mm and 370 mm,
respectively.
The discs are made from a
specially treated carbon ­fibre
compound that is silicated
in a high ­vacuum process at
approximately 1,700 °C. The
resulting material is not only

much harder than cast iron, it
is also more resistant to heat. Even at high temperatures, the
thermal resistance of the PCCB
disc ensures outstanding dimen
­
sional stabilit y. The ceramic
material is totally resistant to
corrosion and offers excellent
acoustic damping properties.
PCCB enables shorter braking
distances – no mat ter how tough
the driving conditions. The pedal
response is fast and precise with
only moderate input required. Excellent fade resistance ensures
greater balance when slowing
from high speed.
The key advantage of PCCB is

a total weight saving of approxi ­
mately 50% compared with
equivalent cast ­iron discs. As well
as enhancing performance and
fuel economy, the unsprung and
rotating masses are lightened.
The results: greater comfort
and road ­holding on uneven road surfaces plus bet ter handling
and agility.
Optional for all new Cayenne
models.
Recuperation.
The electronic engine manage ­
ment system on the new Cayenne S
Hybrid controls the braking
process so that, when the brake
pedal is actuated, as much
expended energy as possible
can be harnessed by the electric
machine’s generator and stored
in the 288 ­Volt nickel metal
hydride (NiMH) bat tery. This is
referred to as recuperation.
Safety and environment | Safet y · 65
64 · Safety and environment | Safet y

PSM has three additional func­
tions that help reduce braking
distances. If the throt tle pedal
is released suddenly, PSM

automatically readies the braking
system. The pressure in the
brake lines is marginally increased,
bringing each of the pads into
light contact with the correspond ­
ing disc. If the driver goes on
to apply the brakes, the calipers
respond more quickly and the
braking distance is reduced. In an emergency stop – i.e. when
the pressure on the brake pedal
exceeds a certain threshold –
the brake assist function uses the
PSM hydraulics to apply maximum
braking force at all four wheels.
For added safet y, the system
also readies the brakes whenever
a decreasing distance to the
vehicle in front is detected. The
optional adaptive cruise control
and PSM interact to prefill the
brakes.
Even if adaptive cruise control is
inactive, the system registers the
speed of the vehicle in front and
automatically readies the braking
system. In addition, the system
alerts the driver to the decreasing distance by briefly tugging on
the brakes.
PSM also features a trailer
stabilisation function – for a
significant contribution to car
and trailer safet y.
Within the laws of physics, it
compensates for load transfer
caused by throt tle and brake

inputs up to the maximum degree
of lateral acceleration. It also en ­
hances the car’s driving dynamics
and directional stabilit y when
accelerating on inconsistent road
surfaces.
Other features include a special
control strategy in the ABS
for braking on loose surfaces.
By briefly locking the wheels, a wedge is formed ahead of each
t yre which provides additional
purchase to help slow the car,
e.g. on gravel or snow.
For a more involving driving

experience, PSM can also be
disabled, but remains active in
the background.
Standard on all new Cayenne
models.
accele

ration of the car. Using
this information, it is possible to
calculate the actual direction of
travel at any given moment. If
the car begins to oversteer or
understeer, PSM applies selective
braking on individual wheels to
restore stabilit y. If necessar y,
PSM can also intervene in the
engine management system to
temporarily modif y the amount of
drive transmit ted to the wheels.
Porsche Stability Management
(PSM).
Porsche Stabilit y Management
(PSM) is an electronic control
system that uses a range of
functions – including anti ­lock
braking (ABS) – to help stabilise
the vehicle (and trailer, if fit ted)
in hazardous road scenarios.
Throughout each journey, sensors
monitor the direction, speed,
yaw velocit y and lateral
Preparing for the road ahead.
With a little help from PSM.
Safety and environment | Safet y · 67

Weight reduction is a key aspect
of our design philosophy derived
from our rich racing heritage.
Part of our R&D Centre, the
Motorsport Department is locat ­
ed in Weissach where it shares
premises with the Automotive Industry Exhaust Emission Centre
(ADA).
Just a coincidence? We call
it symbiosis.
In practice: the new Cayenne is
up to 185 kg lighter, depending
on the model.
1) This was achieved
through new weight ­saving devel ­
opments and materials, new pro ­
duction technologies, advanced
functionalities and concept
modifications. By using lighter materials, for example, we have
halved the weight of the tailgate.
New materials are also a feature
of the axle construction, with
steel being replaced where pos­
sible by light weight alter
natives
such as aluminium and plastic.
The benefits for the driver:
greater agilit y and driving
dynamics – with lower fuel
consumption. Ef ficiency at
its best.
This is achieved using advanced
engine concepts featuring tech ­
nologies such as DFI (p. 38),
VarioCam Plus (p. 37), the auto
start /stop function (p. 36), the
parallel full hybrid drive and con ­
sistent light weight construction.The concept behind every car we
build is based around the pursuit
of performance. This has been
the case since 1948. Another
of our traditional core values
is efficiency. At Porsche, we

are continually striving to find a
successful balance bet ween
the t wo.
Great achievements are something to be proud of.
Even more so if they benefit the world around you.
Environment.
1) Compared to previous model.

has a separate control system
which the engine management
system uses to establish the
optimum amount of fuel – for
effective emissions control.
The exhaust­gas recirculation on
the Cayenne Diesel routes part
of the exhaust gas back into the
combustion process, resulting
in lower peak combustion tempera ­
ture
and therefore lower nitrogen
oxide emissions. An oxidation
catalyst also forms an integral part of the process along with

a diesel particulate filter. This
ensures that the new Cayenne
Diesel meets the EU5 emissions
standard.
Fuel and fuel economy.
Increasing performance while
enhancing fuel economy. The
new Cayenne comes in a choice
of three dif ferent drive systems
each featuring state ­of ­the ­art
technology for high ef ficiency and
relatively low fuel consumption.
The petrol ­engined models
already operate on fuels with an
ethanol content of up to 10%. The diesel engine is compatible
with a biodiesel blend of max. 7%.
This further improves the carbon
dioxide balance since the plants
grown for the production of
biofuels absorb carbon dioxide
from the atmosphere. As you
can see, for the benefit of the
environment, we are continually
working on making our cars more
ef ficient – as well as compatible
with alternative fuels. While
ensuring that they remain one
thing: a thoroughbred Porsche.
Fuel system.
We have also applied the highest
standards in order to protect
the environment from fuel
evaporation. The non ­return

fuel supply system provides a
considerable reduction in vapour
emissions. The lines carrying
vapour are made from multi ­layer
plastics. A large active ­carbon
filter and multi ­layer plastic fuel
tank help reduce evaporation still
f u rt h e r.
Standard on the new Cayenne,
new Cayenne S, new Cayenne S
Hybrid and new Cayenne Turbo.
advanced drive concepts –
from petrol and diesel engines to
our new parallel full hybrid drive.
This is further aided by the rapid
warm ­up cycle of the cataly tic
converters. The optimum operat ­
ing temperature is reached earlier
so emissions are reduced sooner
when starting from cold.
On the petrol ­engined and hybrid
models, another important feature
is the use of t win oxygen ­sensor
circuits. Each bank of cylinders Exhaust emissions.
The new Cayenne models are
all equipped with the latest emis ­
sions technology. As a result,
they comply with the stringent
European exhaust emissions
standard, EU5.
Whatever the class, every Porsche
combines high performance
with comparatively moderate
emissions. On the Cayenne
models, this is achieved using
Porsche engines.
Performing for today – and the future.
Safety and environment | Environment · 73