2009 PORSCHE 911 torque

Variable Turbine Geometry
(V TG).
The 911 Turbo and 911 Turbo S
models are straightforward, almost
mat ter-of-fact, when it comes
to handling power. V TG has con -
tributed enormously to this.
The variable turbine geometry of
the t win water-cooled exhaust gas
turbochargers goes a long way
to resolving the conflict of aims of
normal turbochargers. With this
technology, the gas flow from the
engine is channelled onto the
turbines via electronically adjust -
able 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. The
guide vanes are controlled by the
engine management system.
The result is a high turbine speed
– and therefore higher boost
pressure – even at low engine
rpm. With more air available, the
combustion is increased, yielding
greater power and torque.
Maximum torque is reached at
lower rpm and is retained across
a wider rev range. Both engine
variants deliver a torque of just
650 Nm from as low as 1,950 rpm.
In the case of the 911 Turbo
models, this torque is available
up to 5,000 rpm. The increased
maximum torque of 700 Nm in
the 911 Turbo S models is avail -
able bet ween 2,100 rpm and
4,250 rpm.
When the boost pressure reaches
its maximum value, the guide
vanes are opened further. By var -
ying the vane angle, it is possible
to achieve the required boost pressure over the entire engine
speed range. As a result, there is
no need for excess-pressure
valves as found on conventional
turbocharged engines.
In the 911 Turbo models, engine
performance can be further
enhanced by selecting the SPORT
but ton on the optional Sport
Chrono Package Turbo. Under

full acceleration, the maximum boost pressure in the lower and
medium speed ranges is tempo
-
rarily increased by approximately
0.2 bar. As a result, engine torque
is temporarily boosted by 50 Nm
to a maximum of 700 Nm. The
911 Turbo S models, by contrast,
are configured to operate with a
higher boost pressure level, which
means that their maximum torque of 700 Nm is available for an
unlimited period.
These values are sure to impress.
Yet, combined with the fuel
economy achieved despite the
high power output, they are
even more impressive. Because
power alone is not enough.
Guide vanes closed
Guide vanes open
Performance | Engine
Variable Turbine Geometry (VTG)
· 36 ·· 37 ·

VarioCam Plus.
VarioCam Plus is a variable valve
timing system on the inlet side
which also features t wo -stage
valve lift. For excellent smooth-
running performance, bet ter fuel
economy and fewer emissions.
And greater power and torque.
The timing of each valve is step-
lessly and electro -hydraulically
controlled by means of a rotary
vane adjuster.
For optimum responsiveness
during the warm-up phase,
VarioCam Plus will select the
higher valve lif t set ting and retard
valve timing. At medium revs
and low engine loads, the lower
valve lif t set ting is selected
and timing advanced in order to
reduce fuel consumption and
emissions. For maximum power
and torque, the higher lif t set ting
is selected and the timing of the
valves is advanced.
Engine management.
The EMS SDI 3.1 engine manage -
ment system ensures optimum
performance at all times.
It is responsible for all engine-
related functions and assemblies,
resulting in improved fuel
economy, emission levels and
performance, regardless of
driving st yle.
Another important task performed
by the engine management
system is cylinder-specific knock
control. Since conditions tend
to vary across the engine, each
cylinder is monitored separately.
If a risk is detected, the individual
ignition timing is adjusted to
protect the cylinders and pistons
at high engine speeds and loads.
The EU-compliant on-board
diagnostics system provides

continuous fault detection as well as early warning for the exhaust
and fuel supply systems. This
actively reduces harmful emissions
while maintaining consistent rates
of fuel consumption.
Ignition system.
The ignition system is a static
high-voltage system. Each indi -
vidual spark plug has a separate
ignition coil, ensuring perfect
combustion every time.
Performance | Engine
VarioCam Plus
· 38 ·· 39 ·

Expansion intake manifold.
More power for less fuel. What
sounds absurd is sometimes
quite simple. You just have to
have the nerve to question
prin ciples that are seemingly
writ ten in stone.
The 911 Turbo and 911 Turbo S
models have an innovative expan -
sion intake manifold that was
used for the first time on the latest
911 GT2. Its unique operating
principle is unlike any thing ever
featured on existing induction
systems. Our ‘expansion’ intake
manifold is a radical development
that is the polar opposite of the
resonance principle used on con -
ventional turbocharged engines.
A resonance manifold increases
engine output by forcing addi
tional
air into the combustion chambers.
To do this, the manifold is designed
in such a way that the air – which
vibrates due to the action of the
valves – is in a compression phase
as it passes through the inlet ports.
Unfortunately, compression not
only increases air volume, it
also increases air temperature
and this has a negative effect
on ignition.
Our expansion manifold simply
turns that principle around. The
internal geometry is radically
different from that on a resonance
intake system. Key modifications
include a longer distributor pipe,
with a smaller diameter, and
shorter intake pipes. As a result,
the air is in the expansion phase
as it enters the combustion

chambers. Since expansion always
cools, the air/fuel temperature is
lower and ignition is significantly
improved – thereby increasing
performance.
Of course, the amount of air that
enters the engine under expan -
sion is less than it would be under
compression. To compensate
for this, we’ve simply increased
the boost pressure. The resulting
increase in temperature – again
through compression – is immedi -
ately offset by the uprated inter -
coolers. Instead of hot compressed air
entering the combustion

chambers, we now have cooler

air generating more power and
torque. As a consequence, there
is a major improvement in engine
efficiency and therefore lower fuel
consumption even under heav y
loads and at high revs.
As we said, sometimes you just
have to question established
ideas.
Exhaust system.
The exhaust system is made
from stainless steel. Its cataly tic
converters are extremely heat-
resistant, yet quick to reach
temperature – and thus optimum
performance – when the engine
is started from cold.
Advanced exhaust gas technology
ensures compliance with stringent
emissions standards, e.g. Euro 5
in EU markets, LEV II/ LEV in the
USA.
Servicing.
The 911 Turbo and 911 Turbo S
models are designed for a long
life. A self-adjusting belt drives
the generator, power-steering
pump and air-conditioning com -
pressor. Valve clearances are
adjusted hydraulically, thus avoid -
ing the need for any adjustment
work. The camshafts are driven
by timing chains that require
no maintenance and the ignition
system, with the exception of
the spark plugs, is also mainte -
nance-free. The cars come with
a t wo -year unlimited mileage
w a r ra n t y.
The long service intervals (see
separate price list) keep costs
and labour times down and save
resources, since fewer service
products and consumable parts
are used.
Performance | Engine
911 Turbo engine and exhaust system
· 40 ·· 41 ·

perfect ratio spread enabling a
smooth transition through the
gears. The gear lever throw is
short and precise, with only
minimal effort required. Thanks
to a dual-mass fly wheel, this

performance is achieved without
any compromise in comfort.
The linkage provides a direct
connection with the gearbox
unit while insulating the lever
from engine vibration.
One final detail – the gear

lever design is exclusive to the
911 Turbo models.
Six-speed manual gearbox.
The six-speed manual gearbox,
available as standard exclusively
for the 911 Turbo models, is
specifically adapted to the unique
characteristics and extremely
high torque of the engine in these
vehicles. Designed primarily
for sports driving, it features a
Hill-start assist.
Hill-start assist comes as standard
for both manual and PDK trans -
missions. It assists the driver in
making a smooth and roll-free
start on an incline.
After braking, the system auto-
matically detects whether the
of manual models), the brake
pressure is reduced once suffi -
cient revs have been generated.
Gear lever
vehicle has come to a stop on a
hill. When the driver releases the
footbrake with the car still in gear,
the brake pressure is retained on
all four wheels for around t wo
more seconds. This temporarily
prevents the vehicle from rolling
backwards. When the driver
accelerates (or accelerates and
releases the clutch in the case
Performance | Transmission
· 46 ·· 47 ·

Porsche Traction Management
(P TM).
Genuine high per formance calls
for more than just a power ful
engine. It also requires an ef fec-
tive means of delivering that
power to the road. One solution
to this is all -wheel drive. An
even bet ter one is the further-
enhanced Porsche Traction
Management (PTM), consisting

of active all -wheel drive with
electronically controlled multi -
plate clutch and including an
automatic brake differential (ABD)
and anti -slip regulation (ASR).
PTM improves vehicle dynamics
even further whilst ensuring that
none of the customar y traction
and driving safet y is lost. The
result is an even more enjoyable
sport y ride combined with
exceptional stability.
Torque is distributed actively
– and exceptionally quickly –
via an electronically controlled
multi-plate clutch. The advantage is that, through
continuous monitoring of the

driving conditions, a more imme -
diate response to changing
scenarios can be achieved. The
status is 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 accelera -
tion of the car, and the current
steering angle. The sensor data
is analysed in ‘real time’, 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
transmit ted to the front axle. At
the same time, ASR prevents the
rear wheels from spinning by
adapting the engine power. When
cornering, the system controls
drive to the front wheels in order
to maintain optimum lateral grip.
On variable-grip surfaces, traction
is enhanced using the automatic
brake dif ferential (ABD). If a wheel threatens to spin, PTM brakes it
via ABD and in doing so transfers
more drive torque to the other
wheel on the same axle.
Assisting PTM is Porsche Stabilit y
Management (PSM). Combined,
these systems provide excellent
torque distribution – and there
-
fore outstanding performance –
in all driving conditions.
The benefits of PTM are most
evident in wet and snow y
conditions. In these conditions,
the 911 Turbo models of fer
breathtaking acceleration. In short, PTM provides greater
active safet y and greater

performance, combined with
exemplary balance.
Performance | Transmission
Active all -wheel drive
· 48 ·· 49 ·

Porsche Torque Vectoring (PTV).
Porsche Torque Vectoring (stand-
ard on 911 Turbo S models,
optional for 911 Turbo models), with variable torque distribution
to the rear wheels and a mechan
-
ical limited-slip rear differential,
is a system that actively enhances
vehicle dynamics and stabilit y. As a function of steering angle
and steering speed, accelerator
pedal position, yaw rate and

vehicle speed, PT V is able to
improve steering response and steering precision significantly

by specific braking of the right or
left rear wheel.
In simple terms, this means that
when the car is driven assertively
into a corner, moderate brake
pressure is applied to the inside
rear wheel. Consequently, excess
drive force, which varies depend -
ing on the braking force applied
to the inside rear wheel, can be
distributed to the outside rear
wheel, and a rotational pulse (yaw
movement) is generated around
the vehicle’s vertical axis. This
assists the steering input and
results in a more assured steering
manoeuvre.
At low and medium vehicle
speeds, the system significantly
increases agilit y and steering
precision, whilst at high speeds,
and in combination with the
mechanical limited-slip differential,
it additionally ensures greater
driving stabilit y. The system, combined with

Porsche Traction Management
(PTM) and Porsche Stabilit y
Management (PSM), also puts

its stabilising ef fect to good use
on road surfaces with varying
levels of grip and on snow and ice.
As PT V increases the car’s
dynamic performance, the system
remains active when driving
on the racetrack, even if PSM
has been deactivated.
Where
efficien cy is concerned,
this
enhanced performance and
stabilit y are achieved without the
need for any additional compo -
nents, apart from the mechanical
limited-slip rear differential. In
other words, a more enjoyable
drive with no additional weight.
Performance | Transmission
· 50 ·· 51 ·

Sport Chrono Package Turbo
with dynamic engine mount
system.
The Sport Chrono Package Turbo
with dynamic engine mount
system is standard on 911 Turbo S
models and available as an
option for 911 Turbo models.

This integrated system provides
simultaneous enhancement for
engine, chassis and transmission.
Key features include a digital
and analogue stopwatch on the
dashboard, a performance dis -
play, a personal memor y function
in the Porsche Communication
Management (PCM), the SPORT
but ton and – in combination with
PDK – the SPORT PLUS but ton,
and an additional display on the
steering wheel which informs the
driver if the SPORT but tons and Launch Control have been acti
-
vated. The 911 Turbo models
additionally of fer the ‘overboost ’
function. This is how it works:
When ‘Sport ’ mode is selected,
the engine management system
creates a much more aggressive
response to pedal inputs. To do
this, it implements an alternative
throt tle map which relates the
pedal position in the foot well to
a wider angle of opening in the
throt tle body. In higher gears, it
uses a hard rev- limiter to protect
the engine under power.
In the 911 Turbo models, under
full acceleration, the maximum
boost pressure in the lower and
medium speed ranges is now
temporarily increased by approx -
imately 0.2 bar. As a result,
engine torque is boosted by 50 Nm to a maximum of 700 Nm for a
limited period. (The 911 Turbo S
models are configured to operate
with a higher boost pressure level,

which means that their maximum
torque is always 700 Nm.)
In addition to the engine, ‘Sport ’
mode is enabled in the standard
Porsche Active Suspension
Management (PASM) suspension.
The dampers become firmer,
enabling faster turn - in as well as
bet ter contact with the road.
In automatic mode of PDK,
the basic gearshif t pat tern is
switched to high-performance
mode. The gear change action is
virtually instantaneous, while the
shift points are timed for maxi -
mum acceleration. Lif t of f the
throt tle – even at high revs – and
the system automatically shif ts
down to apply engine braking. In
manual shif t mode, gear chang -
ing is faster and more dynamic.
Porsche Stabilit y Management
(PSM) is also adapted, with the
intervention threshold raised. As
a result, the car has a more natu -
ral response to lateral and longi -
tudinal forces. Cornering agilit y
is greatly enhanced, when both braking to turn in and applying
power on exit – particularly

in low-speed bends. For even
greater driving pleasure.
For maximum manoeuvrabilit y,
PSM can be partially disabled
while the car is still in ‘Sport ’
mode. PSM simply monitors the
forces acting on the car and
will only intervene in the most
critical scenarios, e.g. when ABS
assistance is required on both
front wheels.
In conjunction with PDK (standard
on 911 Turbo S models), the
Sport Chrono Package Turbo with
dynamic engine mount system
has t wo additional functions that can be activated via the SPORT
PLUS but ton, for a sport y drive
that borders on a motorsport
experience.
The first function is ‘Launch
Control’, which, for example
when per forming laps, helps you
achieve optimum acceleration
from a standing start, a racing
start in other words.
The function works like this:
press the SPORT PLUS but ton
when the transmission is in ‘D’
or ‘M’. Then, with your lef t foot,
press the brake pedal and accel -
erate fully with the right foot.
The car recognises ‘Launch’ mode
from the accelerator kickdown action and adjusts the engine
speed to the optimum level,
which is around 5,000 rpm. At
the same time, boost pressure
is increased to approximately

0.5 bar, engine torque is
increased and the clutch is
applied lightly. ‘Launch Control’
now appears in the steering
wheel display. Now release the
brake as quickly as you can –
and feel the acceleration power
unleashed to the road.
Steering wheel display with PDK and Sport Chrono Package Turbo
Performance | Chassis
· 58 ·· 59 ·

Interior.
Efficient ergonomics is the guid-
ing theme for the interior. The
steering wheel of fers 40 mm of
adjustment for both height and
reach. A multifunction steering
wheel – with or without steering
wheel heating – is available on
request. The distinctively designed gear lever (for the six-
speed manual gearbox) and PDK
gear selector are easy to operate.
Porsche Communication Manage
-
ment (PCM) with a touchscreen is
fit ted as standard, as is the inte -
gral GPS navigation module with
hard drive navigation (page 86).
The new 911 Turbo S models come equipped with an integrated
six- disc CD/ DVD autochanger

and cruise control as standard.
The air- conditioning system with
an active carbon filter is fully
automatic. The leather finish on the seats,
dashboard, doors and rear
side panels is pleasing to the
touch. Available exclusively for
911 Turbo S models as standard
is the choice of t wo -tone leather
interior in either Black and Cream
or Black and Titanium Blue.
The centre console and door
storage compartments provide
storage space for personal items.
Below the passenger airbag are
t wo cup holders and below these
is the glove compartment with
CD storage.
Two 12-volt sockets (including the
cigaret te lighter) provide power
for a range of electrical devices.
Instruments.

The classic Porsche grouping of
five round instruments offers a
clear overview of all key informa -
tion.
The digital display in the centre-
left dial (speedometer) provides
main and trip odometer readings.
The central rev counter, featuring
the ‘turbo’ ‘or turbo S’ logo,
includes the standard on-board
computer display. This multi -
pur
pose field contains a perma -
nent digital speedometer as well
as the upshif t display on manual
models. The following optional information can also be displayed:
boost pressure, average speed,
average fuel consumption, t yre
pressure, current radio station,
navigation instructions and
remaining range till empt y. When
‘Sport ’ mode is selected on

the Sport Chrono Package Turbo
in a 911 Turbo model equipped
with dynamic engine mount
system, the temporary increase
in maximum torque is clearly
indicated by an arrow symbol in
the boost pressure display.
The third display, in the centre-
right dial, shows the time and
outside temperature.
Why do you need huge gestures
when the signs are clear?
Comfort.
An expressive design.
Well conceived technology.

A consistently sporty style.
No gimmicks. Why should the
rules for performance be
any different for the interior?
Personality | Comfort
Instruments in the 911 Turbo with PDK
Interior of the 911 Turbo in natural leather Carrera Red
· 80 ·· 81 ·