2004 PORSCHE 911 TURBO Fuel

locked, the outermost ring –
which is driven by two large
profile cams – is in direct contact
with the valve. When the pin is
removed, the innermost lifter –
operated by a smaller cam
lobe – has sole influence over the
amount of valve lift. 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 selected and timing advanced in
order to reduce fuel consumption
and emissions. The economy of
the engine is particularly
enhanced at lower engine speeds.
For maximum power and torque,
the higher lift setting is selected
and the timing of the valves is
advanced.
From the driver’s perspective, the
results are clear: copious torque
with exceptional fuel economy,
particularly in comparison with
much larger yet similarly rated
engines.
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Drive
VarioCam Plus combines variable
valve timing with two-stage valve
lift on each inlet camshaft. The
resulting benefits include greater
power and torque at all engine
speeds, as well as smoother
running, better fuel economy and
fewer exhaust emissions.Essentially, VarioCam Plus offers
two engines in one. The first is
designed for normal road driving,
the second for high-performance
use. The system switches
seamlessly between the two
as driver inputs change. All
operations are centrally controlled
by the engine management
system. The result: emphaticacceleration and smoother
running.
The two-stage lift mechanism on
each inlet valve consists of an
electro-hydraulically switchable
tappet. Each of the 12 tappets
has two concentric lifters which
can be locked together by means
of a pin. When the tappets are
· 38 ·
VarioCam Plus.
Optimum valve timing, optimum valve lift, in all load conditions.

Engine cooling.
The 911 Turbo engine features
cross-flow water cooling with fully
integrated coolant management.
This technology ensures a
consistent flow of coolant to each
of the engine’s cylinders. All
coolant passages are integral to
the block, thus eliminating the
need for external hoses. Each
cylinder receives a fresh supply
of coolant which has not been
pre-warmed by the engine. As well
as improving reliability, this
helps to minimise maintenance
requirements. 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.
Engine management.
Optimum performance is assured
at all times with the aid of
the Motronic ME7.8.1 engine
management system. On the new
911 Turbo, this powerful ECU is
responsible for all engine-related
functions and assemblies (see
diagram). Key among these are
the Variable Turbine Geometry
(VTG), VarioCam Plus and
electronic throttle system – one
of the essential prerequisites
for the standard Porsche Stability
Management (PSM). The results:
optimum economy, emissions
and performance, regardless of
driving style.Another important task performed
by the engine management
system is cylinder-specific knock
control. By preventing pre-ignition
at high engine speeds, this
function can avert costly damage
to the pistons and cylinders. Since
temperatures tend to vary in
different parts of the engine, each
cylinder is monitored separately.
If a risk is detected, the individual
ignition timing is adjusted.
The EU-compliant on-board
diagnostics system provides
continuous fault detection and
early warning for the exhaust
and fuel supply systems. The
resulting benefits are active
prevention of harmful emissions
as well as consistent rates of
fuel consumption.
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Drive
Input data Used to regulate /control
Engine management system
(Motronic ME7.8.1)
Engine load
Pressure upstream from throttle
Throttle-valve angle
Engine speed (from crankshaft)
Camshaft phase angles
Throttle-pedal position
Lambda signal
Knock sensor signal
Ignition
Fuel injection
Throttle valve
Heating elements in lambda sensors
Fuel pump
Fuel-tank venting
CAN interface to
all-wheel drive control unit 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)
Bypass valve
Secondary air injection
Engine-bay fan
Starter
On-board diagnostics
Air-conditioning compressor
Interface to instrument cluster
Radiator fans
Vehicle speed
Air-conditioning settings
Engine immobiliser status
Clutch pedal switch
Ambient air pressure
Temperatures
– coolant
– airflow upstream from throttle
– engine oil
– air in engine compartment
– ambient air
Exhaust-gas temperature

Fuel injection.
Fuel is supplied to each of the six
cylinders by means of sequential
fuel injection. The timing of each
injection and the volume supplied
to each bank of cylinders are
controlled by the Motronic ME7.8.1
engine management system.
Adjustments are based on a range
of variables, such as throttle
position, engine speed, boost
pressure, coolant temperature
and exhaust gas composition. Theresults are optimised combustion
and fuel consumption. A hot-film
air mass sensor monitors the
density of the incoming air to
ensure the optimum air/fuel
mixture, regardless of weather
and altitude.
Ignition system.
The 911 Turbo is equipped with
a static high-voltage ignition
system. Each individual plug has
a separate ignition coil, ensuring
perfect combustion every time.
The role of distributor is performed
by the engine management
system, which operates the coils
directly. The result: optimum
performance with minimal fuel
consumption.
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Drive

are reduced thanks to lengthy
replacement intervals for both
the engine oil (18,000 miles) and
air filter unit (36,000 miles). The
spark plugs require changing after
36,000 miles or a maximum of
every four years. The generator,
power-steering pump and air-
conditioning compressor are all
driven by a single self-adjusting
belt with a service life of 54,000
miles. The hydraulic tappets
provide automatic adjustment of
all valve clearances, while the
drive chains on the camshafts
and auxiliary shafts will also last
the life of the car.
Basic servicing is required after
18,000 miles or a maximum of
two years on the road. The first
major service is due at 36,000
miles or every four years at the
latest. The results: lower running
costs and virtually uninterrupted
enjoyment from your Porsche.
Exhaust system.
The exhaust system on the
911 Turbo is made from highly
durable stainless steel. The
system consists of two separate
tracts, one for each bank of
cylinders. The catalytic converters
are extremely heat-resistant,
yet quick to reach temperature
(and thus optimum performance)
when the engine is started
from cold.Twin lambda sensors in each of
the exhausts enable continuous
monitoring of the combustion
process. An additional pair of
sensors* is used to measure
the efficiency of the catalytic
converters.
Servicing.
Another pleasant surprise on the
new 911 Turbo is the standard
service schedule. Running costs
The new six-speed manual
gearbox in the 911 Turbo is
specifically adapted to the car’s
high levels of engine torque.
Designed primarily for sports
driving, one immediate
characteristic is the perfectly
judged spread betweensuccessive ratios as you upshift
through the gears. The gearshift
throw is short and precise,
with only minimal force required.
Thanks to a dual-mass flywheel,
this uncompromising setup means
there’s never any compromise
in comfort. The linkage provides
a direct connection with the
gearbox while insulating
the lever from engine vibration.
One final detail – the new gear
lever design – is exclusive to
the 911 Turbo.
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Drive
Six-speed manual gearbox.
Superlative power requires equal precision.
Gear lever exclusive to 911 Turbo* Not in markets with leaded fuel.

Tiptronic S also includes a warm-
up function designed to minimise
exhaust emissions. When the
car is started, the engine speed is
increased so that the catalytic
converters reach their optimum
operating temperature within the
shortest possible time. braking on descent. This, of
course, helps to reduce the
load on the braking system. If
traction is lost under braking
in the wet or on snow, the system
automatically changes up to
restore lateral grip and bring the
car back into line. there is no need to use a kick-
down function. Unlike conventional
automatic systems, Tiptronic S
does not shift up when the throttle
is released, thus enabling
optimum acceleration when exiting
a corner with no loss of stability
due to changes in load. Mid-corner
gearshifts are also prevented,
thereby enhancing stability and
safety. Under heavy braking, the
system shifts down, using engine
braking to slow the car. The
function is enabled during high-
performance use when the driver
releases the throttle to apply
the brake within a period of
1.5 seconds. These active
downshifts enhance the car’s
performance, particularly when
braking for a corner. Under
prolonged braking, additional
downshifts are performed based
on the amount of brake force
applied. An incline sensor
improves uphill acceleration and
makes better use of engine
The 911 Turbo is available with
optional five-speed Tiptronic S
offering a highly rapid gearshift
action. This versatile option offers
fully automatic five-speed
operation as well as direct manual
control.
In manual mode, you can change
gear by hand using gearshift
controls on the steering wheel.
Simply press up to change up,
and down to change down. The
clutch function is fully automatic.In automatic mode, the standard
gearshift pattern, designed
for maximum fuel economy, can
be steplessly varied up to a
dedicated ‘Sport’ configuration
for optimum high-performance
driving. Each gearshift point is
automatically selected based on
current driving style and road
conditions. Within a short space
of time, you’ll develop a feel for
the system and begin to influence
gearshifts using the throttle alone.
The benefits of Tiptronic S are
particularly apparent when
exploring the car’s potential. Even
in automatic, the rapid gearshift
action enables remarkable agility
under acceleration. The imme-
diacy of response, with virtually
no interruption in drive, is now
more than comparable with a
Porsche manual gearbox. At just
3.7 seconds, the new 911 Turbo
with Tiptronic S is 0.2 seconds
quicker to 100 km / h (62 mph)
than the standard manually
equipped car.
While still in automatic, you can
change gear by hand using the
rocker controls on the steering
wheel. If there is no manual input
for a period of 8 seconds,
the system reverts to automatic
mode.
If the car is driven more assertively,
the system automatically selects
the ‘Sport’ gearshift pattern, i.e.,
· 46 ·· 47 ·The new 911 Turbo |
Drive
Tiptronic S gear selector lever Tiptronic S control on steering wheel
Tiptronic S.
Manual and automatic in one versatile solution.

The new 911 Turbo is also
available with an optional high-
performance braking system:
the Porsche Ceramic Composite
Brake (PCCB). Successfully
tested in the toughest endurance
racing, this unique technology
has been further refined for even
greater road performance.The key components in PCCB
are the moulded ceramic discs
(front/rear diameter: 380 mm/
350 mm). The larger front discs
provide greater leverage and
therefore better brake performance.
Thediscsaremadefrom a
specially treated carbon-fibre
compound that is silicated in a
high-vacuum process at 1,700 ºC.
The resulting material is not
only much harder than metal, it
is also more resistant to heat.
Even at high temperatures, the
thermal resistance of the PCCB
disc ensures excellent dimensional
stability. The ceramic material is
totally resistant to corrosion and
offers excellent acoustic damping
properties.The pads are mounted in six-
piston monobloc aluminium
fixed calipers at the front, with
four-piston units at the rear.
The resulting brake forces are
not only extremely high, they are
also exceptionally consistent.
The pedal response is fast andprecise, with only moderate input
required.
The key advantage of PCCB is the
total weight saving over comparable
metal discs of approximately 50 %.
As well as enhancing performance
and fuel economy, this represents
a major reduction in both the
unsprung and rotating masses.
This, of course, produces
additional benefits in terms of
comfort and road-holding on
uneven road surfaces as well as
general handling and agility.
For more information, see thelatest PCCB brochure available
from your Porsche Centre.
· 70 ·· 71 ·The new 911 Turbo |
Safety
PCCB
Porsche Ceramic Composite Brake (PCCB).
When it comes to developing new brake technology,
nothing holds us back.

Porsche Communication
Management (PCM). This
comprehensive system features
satellite navigation with a
separate DVD drive in the
luggage compartment for
the single navigation disc.
The one-touch switches on the
centre console are logically
positioned for optimum ease of
use. All instruments are perfectly
placed within the driver’s field of
vision. The air-conditioning system
is fully automatic and features a
highly effective active carbon filter.
This added convenience gives
you greater freedom to enjoy the
driving experience.
The tinted front glass and generous
rear screen offer excellent fore-
and-aft visibility. The front side
windows have a water-repellent
finish, which automatically
disperses moisture and dirt.
The result: optimum visibility in
poor weather conditions.
Instruments.
The classic arrangement of five
round instruments provides a
clear overview of all key information.
The digital display in the centre-left
dial (speedometer) provides main
and trip odometer readings. The
central rev counter, featuring the
‘turbo’ logo, includes the standard
on-board computer display.
This multi-purpose field contains a
permanent digital speedometer
as well as the following optional
information: boost pressure,
average speed, average fuel
consumption, tyre pressure,
current radio station, navigation
instructions and remaining range
till empty. When ‘Sport’ mode
is selected on the optional Sport
Chrono Package Turbo, the
temporary increase in torque is
clearly indicated using an arrow
symbol in the boost pressure
display. The third display, in the
centre-right dial, contains a
clock and external temperature.
The dot-matrix technology used in
each of these displays provides
a high resolution for icons and
text. Design and legibility are
further enhanced with brilliant
white backlight illumination.
· 78 ·· 79 ·The new 911 Turbo |
Comfort
Interior.
For the pure enjoyment of performance.
The passenger compartment in the
new 911 Turbo is another example
of uncompromising design. As you
would expect, it offers the highest
standards of ergonomics, comfort
and quality. The seats, dashboard,
doors and rear side panels are
finished in leather as standard. Atthe centre of the cockpit is a new
gear lever design that’s exclusive
to the new 911 Turbo.
Other standard features include
a three-spoke sports steering
wheel offering 40 mm of
adjustment for both height and
reach. A three-spoke multi-function
steering wheel – available as
optional equipment – provides
direct access to audio, navigation
and (if fitted) telephone functions.
The standard audio package
is the latest evolution of

Antenna diversity.
The PCM package includes four
separate antennae which are
discreetly incorporated within the
windscreen glass. This simple
solution enables the twin-tuner
radio system to find the strongest
possible signal, thereby enhancing
FM reception.
On-board computer.
The PCM computer offers a wide
range of information, including
average fuel consumption, average
speed, range till empty, journey
time and external temperature.
It can also be used to view data
from the optional Tyre PressureMonitoring (TPM). The computer
is operated using a separate
control stalk, displaying key infor-
mation in the central instrument
dial. The same control stalk
is used to operate the timing
functions in the optional Sport
Chrono Package Turbo.
Electronic logbook.
This optional addition to PCM
enables automatic logging on
every journey of mileage, route
distance, date and time as well as
starting location and destination.
Data can be downloaded from
PCM via an infrared port and
processed on a computer using
software included with the
package. This easy-to-use option
fulfils all the requirements for
automatic logbooks as specified
by the German revenue authorities.
Telephone module.
The optional GSM telephone has
a 12-digit keypad and a hands-
free facility offering excellent callquality. The hands-free microphone
is located next to the steering
column and is ideally positioned
for the driver. The telephone
system supports SMS (text)
messaging as well as card-free
calls to emergency services. An
optional passive (keyless) handset
with leather-trimmed console
enables clearer communication
as well as greater privacy when
making a call.
CDC-4 CD autochanger.
This optional CD autochanger has
a total capacity of six audio
CDs and installs beneath a panel
in the luggage compartment.
An autochanger preparation is
included as standard.
· 88 ·· 89 ·The new 911 Turbo |
Comfort
Passive (keyless) handset