2004 PORSCHE 911 TURBO differential

To apply these benefits efficiently
to the road, we required another
innovation in sportscar design: all-
wheel drive with Porsche Traction
Management (PTM). Using an
electronically controlled multi-plate
clutch, this intelligent technology
provides variable drive to each
axle. The front/rear split is con-
tin
uously adjusted based on current
road conditions and driver inputs.
Although biased towards the rear,
the front receives more power
whenever the situation requires.
Porsche Traction Management
is specifically designed to
optimise driving dynamics. The
additional traction provided by
both the all-wheel drive system
and PTM represents a major
improvement in active safety,
especially in the wet or on snow.
Another benchmark technology
on the new 911 Turbo is the
standard braking system. The
front and rear discs have a
generous diameter of 350 mm.On the optional Porsche Ceramic
Composite Brake (PCCB), the
front diameter is increased to
380 mm.
Other standard features on the
new 911 Turbo include a new
evolution of Porsche Stability
Management (PSM) as well as
Porsche Active Suspension
Management (PASM) featuring
electronic damper control.
A
limited-slip differential is available
for the rear axle as an option.
For even greater performance, the
car can be equipped with the
optional Sport Chrono Package
Turbo. Key features include
an ‘overboost’ function which
provides as much as 60 Nm
of additional torque under
acceleration. When the throttle
is fully open, the boost pressure
is increased temporarily by
approximately 0.2 bar. The
electronic throttle map is
also adjusted to give a more
dynamic response to pedal
inputs.
Other modifications when ‘Sport’
mode is selected include a major
rise in the trigger threshold used
by Porsche Stability Management
(PSM). The all-wheel drive system
featuring PTM provides a similar
increase in driver involvement
by sending a greater proportion
of drive torque directly to the
rear wheels. PASM provides a
stiffer suspension setup enabling
faster turn-in and better road
contact.
Another major development
on the new 911 Turbo is the
car’s lightweight design and
construction. The doors and front
lid are made from aluminium
which offers a range of benefits
in terms of both performance
and economy. Every gram of
weight on every component
is there for a specific reason.
As a result, the standard model (with six-speed manual gearbox)
weighs just 1,585 kg. Even more
impressive are the power-to-
weight ratio of 302.8 bhp per
tonne and surprisingly low fuel
consumption.This powerful potential is, of
course, matched by exemplary
ride quality on every type of
road. This rare combination of
performance and comfort is one of the distinguishing features
of the 911 Turbo.
· 18 ·· 19 ·The new 911 Turbo |
The new 911 Turbo

· 26 ·The new 911 Turbo |
Drive
· 25 · · 24 · · 23 ·
7. Exhaust-gas turbocharger
with Variable Turbine
Geometry (VTG)
8. Intercoolers
9. Pressure pipe
10. Throttle valve
(electronically actuated)
11. Exhaust system
12. Oil filter
13. Engine oil reservoir
(dry-sump lubrication)
1. Radiator module (left)
2. Radiator module (centre)
3. Radiator module (right)
4. Coolant pipe
5. Coolant expansion tank
6. Air filter
14. Generator
15. PASM damper
16. Tandem brake booster
17. 6-speed manual gearbox
18. Front differential
19. Fuel tank1. Oil scavenge pump
2. Oil-pressure pump (obscured)
3. Engine oil reservoir
(dry-sump lubrication)
4. Camshaft adjuster (VarioCam Plus)
5. Intake camshaft
6. Tappets (with hydraulic valve
clearance adjustment)
7. Valve springs
8. Intake valves
9. Nikasil-coated cylinder bore
10. Forged aluminium piston
11. Forged connecting rod
12. Crankshaft
13. Camshaft drive chain
14. Camshaft drive chain tensioner
with guide rail
15. Single-spark ignition coil
16. Spark plug
17. Exhaust-gas turbocharger with
Variable Turbine Geometry (VTG)
18. Exhaust system
19. Catalytic converter
20. Pressure pipe
21. Throttle valve (electronically actuated)
22. Plenum chamber
23. Ancillary drive belt
24. Fluid reservoir for
power-steering system
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4
5
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6
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24
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14
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7810
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using the automatic brake
differential (ABD) function. For
optimum traction, manual gearbox
cars can also be equipped with
an optional mechanical limited-slip
rear differential (see page 56).
Assisting PTM is a new and
specially uprated version of
Porsche Stability Management
(PSM – see page 58). Combined,
these systems ensure optimum
torque distribution – and thus
optimum drive – in every type of
road scenario, including high-
speed straights, hairpin bends and
challenging, variable-grip surfaces.
Under heavy braking where ABS
is required, the multi-plate clutch
severs all front drive so that
each front wheel can be controlled
separately
by the ABS without
being influenced by the rear wheel
dynamics.
The traction benefits of the new
electronically controlled system
are particularly apparent in
the wet or on snow. In these
conditions, the new 911 Turbo
offers breathtaking acceleration.
In short, PTM offers greater
active safety, greater performance,
and even more of the positive
handling and agility you’d expect
from a 911 Turbo.
· 49 ·The new 911 Turbo |
Drive
differential (ABD) and anti-slip
regulation (ASR).
The electronically controlled clutch
is used to vary the drive torque
transmitted to the front axle. The
previous 911 Turbo had a multi-
plate clutch filled with a viscous
fluid, which ‘passively’ determined
the front/rear torque split. On
this latest evolution, the fluid is
replaced by active, electronic
control.While the viscous-fluid system
responds to relative differences in
front/rear axle speed, the new
electronic clutch offers a more
direct response to changing road
scenarios. The status of the car
is continuously monitored with the
aid of on-board sensors. These
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. The sensor data is analysed
in ‘real time’ by PTM, enabling
immediate adjustments in front-end
drive torque as and when required.
If, for example, the rear wheels
lose traction under acceleration, a
greater proportion of drive torque
is automatically transmitted to
the front axle. The integral ASR
function is also used to minimise
wheel-spin. When
cornering,
the system controls drive to the
front wheels in order to maintain
optimum lateral grip. On variable-
grip surfaces, traction is enhanced
· 48 · Electronically controlled multi-plate clutchAll-wheel drive system
Genuine high performance calls for
more than just a powerful engine.
It also requires an effective means
of applying that power to the road.
On the 911 Turbo, this is achieved
by means of permanent all-wheel
drive and an all-new version of
Porsche Traction Management
(PTM). The key mechanical feature
within the AWD system is the
electronically controlled multi-plate
clutch. Integral functions within
PTM include an automatic brake
Electronically controlled all-wheel drive with Porsche Traction Management (PTM).
The intelligent application of power and torque.

The new 911 Turbo is equipped
with Porsche Active Suspension
Management (PASM) as standard.
This electronic active damping
system offers continuous adjust-
ment of the damping force on
each wheel based on current road
conditions and driving style.
PASM has two driver-selectable
setup modes, ‘Normal’ and ‘Sport’,
which share a minimal degree
of overlap. While ‘Normal’ provides
a blend of performance and
comfort, the ‘Sport’ setup mode
has a much firmer range of
settings. The system responds to
changing road conditions and/or
driving style by continuously
varying the individual damping
forces within the parameters
defined for the selected setup
mode (‘Normal’ or ‘Sport’).
PASM uses a range of sensors
to monitor any movement in the
body of the car (e.g., under
acceleration, braking or on uneven
road surfaces). The PASM control
unit uses this data to obtain a
real-time evaluation of the forces
acting on the car. The system
responds continuously with a
corresponding modification of
individual damping force s in
accordance with the selected
setup mode. The results are a
reduction in both pitch and roll
as well as consistent road-holding
from all four wheels.
If ‘Sport’ mode is selected, the
suspension is set to a harder
damper rating. If the quality of
the road surface falls below a
certain threshold, the system
immediately changes to a softer
rating within the ‘Sport’ setup
range. This adjustment enhances
occupant comfort as well as
traction and grip. When the road
surface improves, PASM
automatically reverts to the
original, harder rating.
If ‘Normal’ mode is selected, and
the car is driven more assertively,
PASM automatically switches to
a harder rating within the ‘Normal’
setup range. As the dampers
become stiffer, the car becomes
more stable, ensuring higher
levels of active safety as well as
greater enjoyment from your
Porsche.
Limited-slip differential.
The manual gearbox version of
the new 911 Turbo is available with
an optional mechanical limited-slip
rear differential. Key benefits
include greater rear-end traction
when exiting hairpin bends as
well as on variable-grip surfaces.
It also compensates for changes
in wheel loads caused by throttle
modulation when cornering.
· 56 ·· 57 ·The new 911 Turbo |
Chassis
Porsche Active Suspension Management (PASM).
From ultimate comfort to optimum performance,
all at the push of a button.
Rebound in ‘Normal’ mode –
damper piston with bypass
valve openRebound in ‘Sport’ mode –
damper piston with bypass
valve closed
Compression in ‘Sport’ mode –
damper piston with bypass
valve closedCompression in ‘Normal’ mode –
damper piston with bypass
valve open

This latest evolution of Porsche
Stability Management (PSM)
provides automatic assistance in
critical road scenarios. A powerful
driver aid, it uses a range of
sensors to monitor the direction,
speed, yaw velocity (speed of
rotation around the vertical axis)
and lateral acceleration of the car.
With this information, it can
then calculate the actual direction
of travel. If the car begins to
oversteer or understeer, PSM
applies selective braking onindividual wheels to bring it safely
back into line. Whenever PSM is
required to intervene, an indicator
light in the cockpit is illuminated.
Another scenario in which PSM is
invaluable is when applying the
throttle on wet or other low-grip
surfaces. Here, PSM uses the ABD
(automatic brake differential) and
ASR (anti-slip regulation) functions
in PTM to maintain traction and
stability.Standard equipment on the
911 Turbo, PSM assists with high-
precision inputs that enhance the
athleticism and agility of the car.
When ‘Sport’ mode is selected
on the optional Sport Chrono
Package Turbo (see page 60),
the PSM threshold is raised
higher still enabling greater driver
involvement – particularly
at speeds of up to 70 km / h
(44 mph).
The integral ABS ensures shorter
braking distances in critical road
scenarios. System inputs are
smooth and precise fo r greater
driver comfort. Active safety is
further enhanced with the aid of
two additional brake functions:
electronic brake prefill and brake
assist.
The prefill function is automatically
enabled whenever the throttle
pedal is suddenly released. The
pressure in the brake lines is
marginally increased, bringingeach of the pads into light contact
with the corresponding disc. If
the driver then decides to use the
brakes, the system can apply
the maximum force with virtually
no delay.
The brake assist function is
specifically designed for use in
emergency stops. When the
pressure on the brake pedal
exceeds a predefined threshold,the brake assist function uses
the PSM hydraulics to apply the
pressure required for maximum
deceleration. The result: shorter
braking distances.
For a more natural drive, PSM can
be manually disabled leaving only
the automatic brake differential
(ABD) in place. Although essentially
inactive, PSM remains present in
the background and can intervene
immediately under heavy braking
where at least one front wheel
requires ABS assistance. In ‘Sport’
mode, PSM will only respond
when ABS is active on both front
wheels.
In short, PSM provides the ideal
balance between electronically
assisted active safety and
freedom to enjoy the car’s
potential.
· 58 ·· 59 ·
Oversteer without PSM Oversteer with PSM
Car steers off line
Car steers off line PSM corrects
steering and
stabilises car
PSM corrects
steering and
stabilises car
Understeer without PSM Understeer with PSM
The new 911 Turbo |Chassis
Porsche Stability Management (PSM).
Enhanced stability control for the new 911 Turbo.

· 109 ·The new 911 Turbo |
PersonalisationThe new 911 Turbo |Personalisation
OptionI no. Page
• Special colours•
•Code 103
• Colour to sample
• •Code
• Deletion of model designation
W498
• ParkAssist (parking aid at rear)
• •635 82, 109
• Rear wiper w 425 83
• Grey top tint on windscreen
• •567
• Electric slide/tilt sunroof
• •650 83
• Side skirts painted
• •XAJ 108
• Roof transport system
• •549 84
· 108 ·
The new 911 Turbo has a
comprehensive standard
specification. It also offers
exceptional scope for your
own personalisation ideas.
With the wide range of options
presented here, you can make
the new 911 Turbo unique.
Combined, they enhance the
individuality of your Porsche– inside and out – as well as
its performance and comfort.
Over the following pages, you’ll
find the full range of options listed
by category. For more information
on individual items, please refer
to the 911 Turbo price list.
For the ultimate in personalisation
for the 911 Turbo, ask about thePorsche Exclusive programme
of factory-fitted modifications.
You can also continue to
enhance your car with Porsche
Tequipment aftermarket
accessories.
For more information, please
contact your Porsche Centre.
· 107 ·
911 Turbo with PCCB
Exterior.
• •extra-cost option W no-cost option
For more information on optional equipment, please refer to the 911 Turbo price list.
We’ve realised many dreams with the new 911 Turbo.
Now you can realise yours.
911 Turbo with side skirts painted
ParkAssist Porsche Ceramic Composite Brake (PCCB)
OptionI no. Page
• Tiptronic S•
•249 46
• Porsche Ceramic Composite Brake (PCCB)
• •450 70, 109
• Sport Chrono Package Turbo
• •640 60
• Short shifter
• •XCZ
• Limited-slip rear differential (mechanical)
• •220 56
• Wheels painted in exterior colour
• •XD9
• Stainless steel tailpipes, chrome-plated
• •X54
Engine, transmission and chassis.

L
Leather 104, 112
Limited-slip differential,
mechanical 56
Loudspeakers 90
LSA concept 53
Lubrication 31
Luggage compartment 84
M
Manual gearbox 45
Materials 95
MOST
®bus 90
MP3 playback 86
Multifunction steering wheel 78
Multi-plate clutch,
electronically controlled 48
N
Navigation expansion module 87
Navigations system 87
Noise 97
O
On-board computer 88
On-board diagnostics 40
Optional equipment 108
P
ParkAssist 82
Performance display 60
Personalisation 98
Porsche Active Suspension
Management (PASM) 56
Porsche Ceramic
Composite Brake (PCCB) 70
Porsche Communication
Management (PCM) 86
Porsche Side Impact
Protection (POSIP) 75
Porsche Stability
Management (PSM) 58
Porsche Traction
Management (PTM) 48
R
Rear wiper 83
Recycling 95
Roof transport system 84
S
Safety, active 66
Safety, passive 72
Seats 80
Seats, rear 81
Service 122
Servicing 44, 97
Sport button 60
Sport Chrono Package Turbo 60Sports seats 80
Sports seats, adaptive 80
Steering 54
Stereo lambda control 44
Sunroof, slide/tilt 83
Suspension 52
T
Tandem brake booster 69
Technical data 126
Telephone 89
Timer 60
Tiptronic S 46
Transmission 126
Tyre Pressure
Monitoring (TPM) 55
V
Variable Turbine
Geometry (VTG) 32
Variable valve timing 39
VarioCam Plus 38
Vehicle tracking system 84
W
Water- cooling 40
‘Welcome Home’ lighting 82
Wheels 55
Wood, macassar 115
Wood, sycamore 116
· 129 ·
A
Air conditioning, automatic 79
Airbags 74
Alloy engine 30
All-wheel drive 48
Aluminium Look 118
Antenna diversity 88
Anti-theft protection 84
Audio system 86, 119
AudioPilot
®91
Axle concept 52
Axle, front 52
Axle, rear 53
B
Bi-Xenon lighting 66
Bodyshell 72
BOSE
®Surround
Sound System 90
Boxer engine 28, 30
Braking system 68
C
Carbon 117
Catalytic converters 44
CD autochanger 89, 119
Ceramic brakes 70
Child seats 81
Colours 100
Colours, interior 104
Colours, special interior 105
Communication 119
Cross-flow cooling 40
Cruise control 83
D
Design 20
Driver memory function 63
Dry-sump lubrication 31
DVD navigation drive 87
E
Electronic logbook 89
Emissions control 94
Engine management system 40
Exhaust system 44
F
Factory collection 120
Fire extinguisher 82, 111
Foglights 67
Fuel injection, sequential 42
Fuel system 97
G
GPS navigation system 87
GSM telephone 89
H
HomeLink®83
Hot-dip galvanised sheet steel 73
I
Ignition 43
Instruments 79
Interior 78
K
Knock control,
cylinder-specific 40
· 128 ·
Index