2012 PORSCHE CAYMAN S clutch

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e ngine management.
The electronic engine management
system ensures optimum perfect engine
performance at all times. It regulates all
engine-related functions and assemblies.
The results are optimum power output
and torque with comparatively low fuel
consumption and emissions – whatever
the driving st yle.
One example is the cylinder-specific knock
control. Since engine cylinders never all
work under exactly the same conditions,
the knock control function monitors each one separately. The ignition point is shift
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ed individually, as and when necessary,
so as to protect the cylinders and pistons
at high engine speeds and loads. For
compliance with EU standards, the on-
board diagnostics detect any faults and
defects that may occur in the exhaust
and fuel systems and then display them
on the on-board computer. This also
helps to avoid increased pollutant emis
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sions and unnecessary fuel consumption.
a uto start/stop function.
The auto start/stop function, which is in -
tegrated as standard in the new Cayman
models, switches off the engine when
you stop, select neutral and release
the clutch pedal. In cars with Porsche
Doppelkupplung (PDK), it is simply a
case of applying and holding the brake.
All audio and communication systems
remain switched on. The engine will

restart as soon as you operate the clutch
or, in cars with PDK, release the brake.
This fuel-saving innovation is designed

primarily for use in urban traffic. The auto start /stop function can be deac
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tivated and reactivated using a separate
but ton on the centre console. The func -
tion is deactivated automatically under
particular circumstances, e.g. in the
event of extreme outside temperatures,
activation of the SPORT but ton or low

bat tery charge.
Drive |
Engine
1 Auto start /stop but ton
2 SPORT but ton

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Six-speed manual gearbox.
The new Cayman models are equipped
as standard with the six-speed manual

gearbox. Gearshifts are smooth, precise
and optimally adapted to the respective
engine map. Shift throws are short and
the gear lever is easy to operate, provid -
ing a truly engaging driving experience.
The upshift indicator located in the central
circular instrument helps you to maximise
fuel efficiency.
The ascending centre console reinforces
the authentic sports car feel. It positions
the gear lever close to the steering wheel,
enabling you to change gear as fast and
as ergonomically as possible.
Porsche Doppelkupplung (PDK).
Of course, you could let us take care of
the gearshift strategy so that you can
devote all your at tention to your cornering
strategy.
Available as an option is the completely
retuned 7-speed Porsche Doppelkupplung
(PDK), featuring both manual and auto -
matic modes. The advantages are percep -
tible. Gear changes take place with no
interruption in the flow of power. Sharper
gearshift programs and significantly short -
er shift times produce faster acceleration
than with the manual gearbox. Fuel econ-
omy and comfort characteristics have also
been optimised. In response to a less
assertive driving st yle, shif t points are

recalculated to make use of the more
comfortable and more economical engine
speed ranges, and coasting mode is acti -
vated where possible (p. 44).
This is how PDK works: PDK is essentially
t wo gearboxes in one, thus requiring t wo
clutches. This double clutch arrangement
provides an alternating, non-positive con -
nection between the two half gearboxes
and the engine by means of t wo separate
input shafts. The flow of power from the
engine is transmit ted through one half
gearbox and one clutch at a time, while

the next gear is preselected in the second
half gearbox. During a gear change, there -
fore, one clutch simply opens and the
other closes at the same time, enabling
gear changes to take place within milli
-
seconds.
PDK has seven forward gears at its
disposal. Gears 1 to 6 have a sports
ratio and top speed is reached in sixth

gear. Seventh gear has a long ratio and
keeps
engine speed low to reduce fuel
con
sumption and improve comfort.
1 Gear lever for six-speed manual gearbox
2 Porsche Doppelkupplung (PDK) gear selector
3 Gearshif t switch on spor ts steering wheel
in conjunction with PDK
y ou’ve developed your own strategies for advancement.
So have we.

Transmission.
For fuel consumption, CO2 emissions and efficiency class, please refer to page 131.

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With the SPORT but ton selected, the full
advantages of the new version of PDK
are brought into play: a more immediate
response to throt tle inputs, relatively
short shift times and swift throt tle-blip
downshifts on overrun, such as during
braking into a corner, and always accom -
panied by an emotive engine sound.
With the optional Sport Chrono Package,
PDK is enhanced by ‘Launch Control’
and the ‘motorsport-derived gearshift
strategy’ for even faster and firmer gear
changes and best possible per formance,
thanks to a boost in torque during up -
shift phases. Overrun downshifts provide
extremely sport y braking and accelera -
tion for added excitement.
Coasting.
Efficiency is another area in which the
performance of the new Cayman models
has been further improved. The coasting
function available with Porsche Doppel-
kupplung (PDK) enables you to save even
more fuel where the situation allows.
The engine is decoupled from the trans -
mission to prevent deceleration caused
by engine braking. In this way, optimum
use is made of the vehicle’s momentum,
allowing it to coast for longer distances.
For example, you may want to slow down
from 100 to 80 km/ h (70 to 50 mph) in
anticipation
of the change of speed limit
ahead. As you ease off the accelerator
pedal, PDK deselects the current gear
automatically and you begin to coast in
neutral with minimal input required on
your part until
you have reached your desired speed.
As soon as you operate
the accelerator
or brake pedal, PDK
re-engages the appropriate gear within
fractions of a second. The process
is smooth and seamless, thanks to the
extremely fast
clutch.
Another way to reduce fuel consumption
is to utilise the coasting function on down -
hill gradients that are gentle enough for
you to maintain a constant speed. Efficient
on long journeys, such as on the motor -
way, PDK remains ready to respond as

swiftly and precisely as you would expect.
In short, driving in coasting mode makes
a real impact on fuel consumption without
the need to compromise on comfort or
sporty performance.
Drive |
Tra n s m i ssi o n
For fuel consumption, CO2 emissions and efficiency class, please refer to page 131.