2009 PORSCHE 911 automatic transmission

Porsche Doppelkupplung (PDK).
Derived from motorsport, PDK,
which is standard for 911 Turbo S
models and optional for 911 Turbo
models, achieves one thing
above all else: it provides the
perfect balance bet ween uncom -
promisingly dynamic performance
and exceptional levels of comfort.
It ’s purely about point of view.
The driver’s especially.
PDK, with both a manual and an
automatic mode, enables
extremely fast gear changes with
no interruption in the power flow.
For improved acceleration and significantly lower fuel consump
-
tion – without having to dispense
with the advantages of an auto -
matic.
The driver experiences a sportier,
even more dynamic drive with
more agilit y. Depending on driving
st yle, gear changes range from
exceptionally comfortable to
exceptionally sport y.
Manual gear changes are per -
formed using PDK’s ergono-
mically
designed gear lever or
alternatively, on the 911 Turbo
models, using the switches on
the three-spoke sports steering
wheel: nudge forwards to change
up, pull back to change down.
Fit ted as standard on 911 Turbo S
models and available as an option
for 911 Turbo models is the three-
spoke sports steering wheel
with gearshif t paddles, which is
also capable of operating PDK.
With its motorsport-derived gear -
shif t logic, you pull the right-hand
paddle to shift up and pull the
left-hand paddle to shift down.
PDK has been specially tuned
to the characteristics of the
911
Turbo models and the new
911 Turbo S models. It has seven
gears at its disposal. Gears 1 to 6
have a sports ratio, with the top
speed being reached in 6th gear.
The 7th gear has a long ratio and
helps to reduce fuel consumption
even further.
PDK is essentially t wo half-
gearboxes in one and thus
requires t wo clutches –
designed as a double wet
clutch transmission.
The principle is simple: the
transmission ensures that
the extraordinary engine
power isn’t manifested as a
blaze of noise and smoke.
Unless that’s what you really
want.
Calm. Storm. Which way
round is up to you.
Transmission.
Porsche Doppelkupplung (PDK) gear selector Power flow in 1st gear
Power flow in 2nd gear
Performance | Transmission
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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
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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
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