2006 PORSCHE CAYMAN engine

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At the heart of each car:
something to set the pulse racing.
Powering the Cayman and Cayman S.
Six-cylinder boxer engine.
Both Cayman models have a
mid-mounted six-cylinder boxer
engine featuring VarioCam Plus
technology. Ideally positioned
directly behind the driver, the
‘flat-six’ engine provides an
The new Cayman and the Cayman S |Drive
0 20
40 60 80 100
120 140 160 180
200
220
1500
7500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 1000 240

240 280 290
300
310
320 330 340
350
250 260
270
217 kW (295 bhp)
340 Nm
360
Power (kW)Torque (Nm)
Engine speed (rpm)
Cayman S: 340 Nm between 4,400 and 6,000 rpm, 217 kW (295 bhp) at 6,250 rpm

150 230 250
270
290
310 330 350
3700 20
40 60 80 100
120 140 160 180
200
220
1500
7500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000
170 190
210
1000
180 kW (245 bhp)
273 Nm 240
390
Power (kW)Torque (Nm)
Engine speed (rpm)
Cayman: 273 Nm between 4,600 and 6,000 rpm, 180 kW (245 bhp) at 6,500 rpm
Cayman S: 3.4-litre six-cylinder boxer engine
perfectly augmented by the agility
its position in the car provides.
The new Cayman has a 2.7-litre
engine developing 180 kW
(245 bhp). The 3.4-litre unit in
the Cayman S produces 217 kW
(295 bhp).On both cars, maximum torque
output is available for use over
much of the engine speed range.
The new Cayman has a maximum
rating of 273 Nm between 4,600 and 6,000 rpm. On the
Cayman S, the maximum output
of 340 Nm is available between
4,400 and 6,000 rpm. This
broad band of torque is, in part,a product of the resonance
induction manifold with twin-flow
intake pipe as well as VarioCam
Plus technology (see page 39).
exceptionally low centre of
gravity. Important characteristics
include exhilarating power
delivery, a free-revving throttle,
optimum cylinder charging,
smooth engine running and
superlative all-round performance.
The power of each engine is

· 33 · · 32 ·The new Cayman and the Cayman S |
Drive
The variable valve system
generates additional torque at
lower engine speeds. Other
benefits include greater top-end
power, better fuel economy
and lower exhaust emissions.
Fuel injection and ignition
are centrally controlled by
the Motronic ME7.8 engine
management system. Power
is applied with control and
precision by means of an
electronically operated throttle.
The engine sound, so rich and
distinctive, is also instantly
Porsche.
Cayman

The new Cayman and the Cayman S |Drive
· 34 ·
1. Oil scavenge pump (obscured)
2. Individual ignition coil
3. Camshaft adjuster (valve timing)
4. Control valve for camshaft adjuster
5. Control valve for variable valve lift
6. Inlet camshaft
7. Switchable tappet with hydraulic valve
clearance adjustment
8. Inlet valve
9. Valve spring
10. Exhaust valve
11. Lokasil-coated bore
12. Forged aluminium piston
13. Forged connecting rod
14. Crankshaft bearing bridge
15. Crankshaft
16. Water jacket
17. Combustion chamber
18. Electronically controlled throttle valve
19. Resonance intake manifold
20. Twin-flow intake pipe
21. Twin-flow intake valve
22. Resonance valve
23. Air-conditioning compressor pulley
24. Power-steering pump pulley
25. Ancillary drive belt
26. Water pump pulley
27. Oil feed pump (obscured)
28. Tandem pump
1
2
3
5
4
6
78
15
16
17
18
19
20
21
22
23
24
25
26
2728
14
9
1011
12
13
· 35 · · 34 · 3.4-litre six-cylinder boxer engine (Cayman S)

· 37 · · 36 ·The new Cayman and the Cayman S |
Drive
Integrated dry-sump
lubrication.
This proprietary Porsche
technology ensures consistent
lubrication in even the most
extreme high-speed corners.
Oil is extracted from each of the
cylinder heads by a dedicated
scavenge pump. The oil return
system features narrow-section
lines which de-foam the oil before
it is collected in the integral sump.
A third pump then feeds the oil
back to the lubrication points and
the cycle begins once more. A
stable oil pressure is maintained
throughout the engine, even
during racetrack use.
Oil-level indicator.
Both Cayman models have an
electronic oil-level indicator as
part of the on-board computer
system. The reading is so precise
that a conventional dipstick is not
required.
Engine cooling.
Both flat-six engines have a
cross-flow cooling system with
all coolant channels cast in the
block. With no external hoses
or pipework involved, the system
is much more secure than
conventional designs.
Coolant is supplied separately
to each individual cylinder, so
it never arrives pre-warmed. As
well as maintaining a consistent
engine temperature, this means
the valves are much less
susceptible to wear. Important
benefits include greater engine
reliability, less risk of knocking,
better fuel economy, lower
emissions and reduced mechanical
noise.
Engine management system
with electronic throttle.
The Motronic ME7.8 engine
management system is the
primary source of control for
all engine-related systems and
processes, e.g., ignition and
fuel supply. It is an essential
prerequisite for enhanced
performance in all operating
conditions. The electronic throttle
is not only more precise, it can
modulate the volume of incoming
air to compensate for sudden load
transfer (e.g., when lifting off the
throttle before braking). Electronic
engine management ensures
better power delivery from a
standing start and a smoother rev-
limiter action. It also coordinates
the various sub-systems within the
Used to regulate /control
Engine management system
(Motronic ME7.8)
Engine load
Throttle-pedal position
Oxygen sensor signals
Engine speed (from crankshaft)
Inlet camshaft phase angle
Knock sensor signals
Vehicle speed
Air-conditioning settings
Engine immobiliser status
Ambient pressure
Sport Chrono button
Temperatures
– coolant
– intake air
– engine oil
– air in engine compartment
Ignition
Fuel injection
Idling via throttle
and ignition
Heating elements in oxygen sensors
Fuel-tank venting
CAN interface to instrument cluster,
transmission control unit, stability control system, etc.Moment interface to
Porsche Stability Management (PSM)
Input data
Twin-flow valve in intake manifold
Resonance valve in intake manifold
Inlet camshaft phase angle
Inlet valve lift
Secondary air injection
Engine fan
Starter
Diagnostics
Air-conditioning compressor
standard Porsche Stability
Management (PSM), e.g., anti-slip
regulation (ASR) and the automatic
brake differential (ABD). Other
important functions include
coordination and control of the
optional Tiptronic S transmission,
the oxygen sensors in the exhaust,
variable valve timing (VarioCam
Plus) and cylinder-specific knock
control.
Cayman S

· 39 · · 38 ·VarioCam Plus The new Cayman and the Cayman S |
Drive
higher torque at low rpm, a flatter
torque curve, and greater top-end
power. It also brings an additional
dimension to the unique engine
sound.VarioCam Plus.
VarioCam Plus combines variable
valve timing with two-stage lift
on the inlet side. 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, the system creates
two engines out of one, switching
seamlessly between them as
driver inputs change. All operations
are centrally controlled by
the Motronic ME7.8 engine
management system. The result:
rapid acceleration and balanced
running characteristics.
The two-stage valve lift mechanism
on the inlet side incorporates
a series of electro-hydraulically
switchable tappets. Each of
the 12 tappets consists of two
concentric lifters which can be
locked together by means of a
pin when required by the engine
management system. When the
tappets are locked, the outermost
ring – which is driven by two large-
profile cams – is in direct contact
Two-stage resonance intake
manifold.
The intake manifold has a twin-flow
pipe with two-stage valve which
opens and closes at predefined
engine speeds. An additional
‘resonance’ pipe connecting the
twin plenum chambers is used
to alter the geometry within the
manifold. The resulting vibration in
the incoming air helps to maximise
cylinder charging and create the
optimum air/fuel mix. The results:
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 each inlet camshaft.
To improve responsiveness when
starting from cold, VarioCam Plus
will raise the amount of lift and
retard the timing of the valves.
At medium revs and minimal load,
the valve lift is lowered and timing
advanced to help minimise fuel
consumption and emissions.
To achieve maximum power and
torque, the lift is raised and the
timing advanced.
Cayman

· 41 · · 40 ·The new Cayman and the Cayman S |
Drive
Ignition system.
The ignition system in the Cayman
and Cayman S features static
high-voltage technology. Separate
coils on each of the plugs ensure
perfect ignition every time. With
no central coil, there is no need
for leads, which are a frequent
source of faults. All six coils are
directly controlled by the engine
management system. This
Cylinder-specific knock control.
Since temperatures tend to
vary across the engine, each
cylinder is monitored separately
for unwanted pre-ignition of the
air/fuel mix. If a risk is detected
in one or more cylinders, the
timing is adjusted on the
corresponding spark plug.
The system is effective under
all engine conditions, including
extremely heavy loads at low
rpm.
Exhaust system.
Both Cayman models have a
specially designed stainless steel
exhaust system. Gas is passed
from each bank of cylinders
through twin cross-linked silencer
units and exits the car through
a central tailpipe. A system of
four oxygen sensors – one before
and one after each of the two
pre-catalytic converters – provides
separate monitoring of the gas
composition and catalyst
performance for each cylinder
bank.
arrangement means they can
also be integrated with other
electronic-based systems. If the
optional Tiptronic S, for example,
requests smoother downshifts,
the system responds within a
fraction of a second and adjusts
the ignition timing.
Since a twin-tract layout allows a
higher rate of throughput than a
conventional exhaust, the system
also has a positive impact on
overall power and torque. It also
contributes to the distinctive
engine sound – on starting, at
idle and across the entire engine
speed range.
For even more powerful acoustics,
both cars can be equipped with
an optional sports exhaust system.
Servicing.
Regular servicing is extremely
important on any high-precision
machine. In the case of a
Porsche, it is equally important
to give you maximum enjoyment
from your car. We therefore aim
to reduce servicing requirements
and extend all service intervals.
The generator, power-steering
pump and air-conditioning
compressor are all driven by a
single, self-adjusting belt. Under
normal usage, the drive chains
for the cam and auxiliary shafts
are entirely maintenance-free.
The ignition system is also
maintenance-free, with the sole
exception of the spark plugs
(60,000 miles). The engine oil
interval is 20,000 miles, while
hydraulic tappets provide
automatic clearance adjustment
on each of the 24 valves.
In short: when we design a car
for the road, that’s where we
intend it to stay.Exhaust system
Dual-tube tailpipe (Cayman S) Single-tube tailpipe (Cayman)Cayman

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11 2
gearbox is supported laterally by
two additional mounts. All three
mounts are hydraulic in design,
using a fluid-filled element to
dampen vibration and noise. The
mounts are effective against both
high and low-frequency vibration.6. Resonance intake manifold
7. Coolant expansion tank
8. Electronically controlled
throttle valve
9. Connecting duct
10. Silencer11. Connecting tube
12. Oil filler neck
13. Air filter intake duct 1. Radiator module
2. Brake booster
3. Gearshift /gear selector lug
4. PASM damper
5. 6-speed manual gearbox/
5-speed Tiptronic S Engine and gearbox mounts.
Both Cayman models use a
system of three hydraulic mounts
to support the engine and
gearbox. The engine is held by
a single mount located centrally
at the front of the unit. The
The new Cayman and the Cayman S |Drive
Cayman S

· 45 · · 44 ·
Tiptronic S.
Both Cayman models are available
with five-speed Tiptronic S as
optional equipment. This versatile
system combines an automatic
transmission with the option of
manual gearshifts.
For manual control, simply slot
the gear selector into the manual
gate and use the gearshift controls
on the steering wheel. Press up
to change up, and down to change
down. Gearshifts are performed
in around 0.2 seconds with
virtually no interruption in drive.
The action is comparable with
that of a manual gearbox.
Switch to automatic, and you can
still change gear by hand using
the rocker controls on the steering
wheel. This race-derived function
is particularly useful during
overtaking manoeuvres. If there
is no manual input for a period
of eight seconds, the system will
revert to automatic mode. The
drive position and gear selection
are displayed at all times on a
dedicated cockpit display.
In automatic mode, Tiptronic S
can choose from a range of
gearshift points for each individual
gear. 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 road
conditions and driving style. 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
performance. Even in automatic,
the rapid gearshift action
enhances the agility of the car.
The new Cayman and the Cayman S |Drive
Manual gearbox with
dual-mass flywheel.
Both the Cayman and Cayman S
are specifically designed for a more
immediate driving experience. A
crucial element within that concept
is the standard manual gearbox.
The new Cayman has a five-speed
unit as standard equipm
ent. The
optional Sport package combines a
How do we make the most of engine performance?
By knowing how to apply it.
Transmission.
mechanical noise and thus greater
focus on the natural sound of the
engine. The flywheel is mated to
a hydraulically operated clutch,
while the final drive ratio has been
carefully selected for optimum
sports performance. The gearshift
mechanism is cable operated
so as to insulate the lever against
vibration from the engine and
gearbox.
Other useful functions include a
warm-up programme, automatic
selection of the ‘Sport’ gearshift
pattern by means of rapid throttle
inputs, gearshift suppression
during cornering manoeuvres,
automatic downshifts under heavy
braking, an incline sensor
(improves uphill acceleration and
downhill engine braking), a nd
automatic upshifts when traction
is threatened under braking in
the wet.
If the optional Sport Chrono
Package is enabled, the gearshift
action is even more direct and
responsive. If you happen to be
driving in manual mode, automatic
upshifts are restricted.
six-speed manual gearbox with
Porsche Active Suspension
Management (PASM – see page
52). The Cayman S has a six-speed
unit as standard. Both gearbox
types have a short-throw action
and a balanced spread of ratios
which are specially adapted to
the individual character of each car.
A dual-mass flywheel ensures
smoother delivery with reduced
Tiptronic S gear selector Tiptronic S control on steering wheel
Cayman S