2010 PORSCHE BOXSTER S engine

· 32 ·· 33 ·
Boxster and Boxster S
Lightweight construction.
Both Boxster models are equipped
with alloy engines. Ingenious
design down to the finest detail
has enabled weight – and conse-
quently fuel consumption – to be
reduced. Integrating the camshaf t
bearings fully into the cylinder
heads is just one example of the
ef fective light weight construction
measures that have been imple -
mented.
Integrated dry-sump lubrication.
Integrated dry-sump lubrication
guarantees a reliable oil supply
while reducing engine tempera -
tures, even in sportily driven cars.

The oil reservoir is located inside
the engine. Four oil pumps trans -
port the oil from the cylinder heads

directly into the oil sump. A fif th
pump in the oil sump directly sup -plies the lubricating points in the
engine. To reduce power losses
and increase efficiency, an elec
-
tronically controlled oil pump
supplies the engine lubrication
points as and when required.

This means that the oil pump does
not work so hard when there is
less demand for lubrication. The
benefits of an on-demand oil
supply system are optimum effi -
ciency combined with a reduction in both fuel consumption and

CO
2 em issio ns.

For the engine, these detailed
solutions mean a consistent

oil supply, regardless of gravita -
tional loads, even in the most
demanding track conditions.
Engine cooling system.
Our cross-flow cooling system,
as used in motorsport, supplies
each cylinder uniformly with cool -
ant. Valves are thus protected
against overload and premature
wear, which minimises the
engine’s tendency to knock and
reduces emissions, fuel con -
sumption and engine noise.
Boxster | Drive

· 34 ·· 35 ·
Boxster
Boxster
Boxster
Engine management system
with electronic throttle.
The electronic engine manage -
ment system ensures optimum
engine performance under all
operating conditions. It regulates
all engine-related functions and
assemblies (see diagram). The
results: optimum performance
and torque with reduced fuel con -
sumption and emissions.
Another important function of the
system is cylinder-specific knock
control. Since the six cylinders
never all work under precisely
the same conditions, they are
monitored individually by the
knock control. If necessary, the
ignition point is shifted individu -
ally to protect the cylinders and
pistons at high engine speeds
and loads. The on-board diagnos -
tics, which are compliant with
European standards, ensure
timely detection of any faults and
defects that may occur in the
exhaust and fuel system in good
time and notify the driver
immediately. This also prevents
increased pollutant emissions
and
unnecessary fuel consumption.
Two-stage resonance intake
manifold.
The intake manifold with dual-flow
distributor pipe has an adjustment
valve which closes and opens at
set engine speeds. A t wo -stage
tuning effect creates oscillation
of the air mass in the intake

system, which in turn generates
a turbocharging effect and opti -
mises induction.
These t wo effects combine to
produce higher torque at low
engine speeds, a flat ter torque
curve, and increased power
output at high engine speeds.
The acoustic properties of the
system are second to none,
producing the characteristic
Boxster sound.
Boxster | Drive
Input data Used to regulate/control
Engine management system
ME 7.8/Boxster – SDI 3.1/Boxster S
Engine load
Lambda sensor signals
Engine speed (from crankshaft)
Inlet camshaft phase angle
Knock sensor signals
Vehicle speed
Pressures
– Engine oil
– Fuel
– Ambient air
Air-conditioning settings
Accelerator pedal
Temperatures
– Coolant
– Intake air
– Air in engine compartment
– Engine oil
– Ambient air
Ignition
Heating of lambda sensors
Fuel pump (Boxster)/fuel pumps
controlled on - demand (Boxster S)
Camshaft position
Fuel-tank venting
Engine fan
Starter
Continuously variable oil pump
Fuel pressure (Boxster S)
Throttle valve
Throt tle -valve angle
Idling via throttle valve
and ignition
Manifold injection (Boxster)/
direct fuel injection (Boxster S)
Valve lift switchover
(VarioCam Plus)
Secondary-air injection (Boxster)
CAN inter face with driving dynamics control, transmission control, immobiliser, instrument cluster, climate control,
SPORT button, SPORT PLUS button, sports exhaust system button, diagnostics, etc.

· 36 ·· 37 ·
VarioCam Plus.
VarioCam Plus combines variable
valve timing with t wo -stage lift
on the inlet side. This results in
smoother running, bet ter fuel
economy and lower exhaust emis-
sions. As well as greater top - end
power and low-end torque.
This two-in-one engine concept
seamlessly adapts in response to
driver input. The result: instant
acceleration and extremely smooth
running.

The variation in intake timing is
steplessly controlled by means of
an electro -hydraulic rotary vane adjuster at the head of the corre
-
sponding camshaft.To improve throt tle response
during the warm-up phase, Vario -
Cam Plus selects high valve lifts
with retarded valve timing. In the
middle and low load ranges, low
valve lifts with advanced timing
Boxster | Drive
reduce fuel consumption and
exhaust emissions. High valve
lifts generate high torques and
maximum output.
VarioCam Plus Boxster S and Boxster
Ignition system.
The ignition system in the Boxster
models is designed for high-
voltage static distribution. The
individual ignition coils, located
on the spark plugs for optimum
ignition reliabilit y, are controlled
directly by the engine electronics.

· 42 ·· 43 ·
The optional Porsche Doppel-
kupplung (PDK), with both man -
ual gearshift and an automatic
mode, enables smooth gear
changes with no interruption in
the flow of power. This results

in significantly faster acceleration
and lower fuel consumption, without having to sacrifice the
ease of automatic transmission.
In total, PDK has seven gears at
its disposal. Gears 1 to 6 have a
sports ratio and top speed is
reached in 6th gear. The 7th gear
has a long ratio and helps to

For people who have no time to spare.
Even when changing gear.
Porsche Doppelkupplung (PDK).
reduce fuel consumption even
f u rt h e r.
PDK is essentially t wo half gear-
boxes in one and thus requires
t wo clutches – designed as a
double wet clutch transmission.
This double clutch provides an
alternating, non-positive connec -
tion bet ween the t wo half gear -
boxes and the engine by means
of t wo separate input shafts
(input shaft 1 is nested inside the
hollowed-out input shaft 2).
The flow of power from the
engine is only ever 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, therefore, a con
-
ventional shif t no longer takes
place. Instead, one clutch simply
opens and the other closes at
the same time. Gear changes
can therefore take place within
milliseconds.
Clutch 1 controls the first half
gearbox, which contains the odd
gears (1, 3, 5, 7) and reverse.
Clutch 2 controls the second,
Boxster | Drive
which contains the even gears
(2, 4, 6).
Porsche Doppelkupplung (PDK)
in detail.
The crankshaf t transmits engine
torque to the dual-mass fly wheel
which is then channelled through
the clutch housing and onto the
multi-plate clutches, or to be more
precise, the outer disc carrier.
4
6
2
1
R
7 3
5
Porsche Doppelkupplung (PDK)
Boxster S

· 44 ·· 45 ·
Under oil pressure, clutch 1
closes and forms a frictional
connection with input shaf t 1.
The torque is now transmit ted
through the first half gearbox
– and then the dif ferential – to
the rear axle. At this stage,
PDK has already preselected
the next gear in the second
half gearbox. Engine torque
is already acting on the other
outer disc carrier and, in
response to a gear change
signal, the overlap shift is initi -
ated, i.e. as clutch 1 opens,

clutch 2 closes. The non-positive
connection with input shaft 2
is
established, and power is
trans
mit ted to the wheels.
The gear which is engaged is
displayed on the instrument
cluster.
Depending on the gearshift
programme, the gear change
is optimised for comfort or for
sport y handling and takes place
in a mat ter of milliseconds.

The advantage over a fully manual
transmission is the considerably
faster rate of acceleration for the
same rate of fuel consumption.
Boxster | Drive
The advantage over a fully auto -
matic transmission
is the per -
ceptible increase in driving
dynamics – with a similar level of
comfort, and a distinct reduction
in fuel consumption.
The com -
pact dimensions of the gearbox
reduce rotational
masses which
means a more direct engine
response, and the system is
more lightweight.
PDK function diagram
This, along with the long-ratio
7th gear, helps to achieve
reduced fuel consumption and
emission figures comparable with
those of a manual gearbox.
With the optional Sport Chrono
Package, PDK is enhanced by
the
‘Launch Control’ and ‘motor-
sport- derived gearshif t strategy’
functions (p. 57). In essence, PDK combines sport
i
-
ness with efficiency and comfort.

What does all this mean for you?
Uninterrupted driving pleasure.
Multi-plate clutch 1
Multi-plate clutch 2
Semi -gearbox 2
(2nd, 4th, 6th gear)
Rear semi-gearbox 1
(1st, 3rd, 5th, 7th, R gear)
Differential
Motor
Rear wheel
Rear wheel
Boxster

· 46 ·· 47 ·
Three-spoke sports steering
wheel with gearshift switches.
In conjunction with the optional
Porsche Doppelkupplung (PDK),
the standard three-spoke sports
steering wheel features t wo
ergonomic switches. One press
with the thumb and the PDK
shif ts up. One pull with the index
finger and the PDK shif ts down.
Either the right or left hand can
be used.
When combined with the optional
Sport Chrono Packages (p. 56),
an additional display is located
above the airbag module telling you whether the SPORT, SPORT
PLUS and Launch Control func
-
tions are activated.
Three-spoke sports steering
wheel with gearshift paddles.
If you wish, you can now change
gear motorsport-st yle. The
paddles are made from a strong
alloy and are ergonomically
located behind the steering wheel
spokes. Pull the right-hand paddle
and the PDK shif ts up. Pull the
left-hand paddle and the PDK
shifts down.
Visually, the steering wheel is
distinguished by its distinctive,
high - qualit y t win -spoke design
and silver-coloured galvanised
spoke cover. The airbag module
is finished in the same colour
as the steering wheel rim.
Displays in the left and right-
hand steering wheel spokes tell
you whether the SPORT, SPORT
PLUS and Launch Control func -
tions are activated. Another

feature reminiscent of the world
of motorsport is the top centre
marking on the steering wheel
rim.
Boxster | Drive
Gear selector for PDK.
The gear selector for PDK im-
presses not only with its unique
design, but above all with its
superior functionality enabling
you to change gear manually.

Press forwards to shift up, pull
backwards to shift down. Even if
the gear selector is set to auto -
matic mode, you can still change
gear manually using the switches
on the steering wheel.
Six-speed manual gearbox.
Fit ted as standard is a six-speed
manual gearbox which is per -
fectly matched to the character -
istics of the engine. The shif t
throw is short and precise, the
tuning is sport y – as befits the
character of the Boxster models.
The dual-mass fly wheel mini -
mises engine noise and the con -
trol cable mechanism prevents
vibrations from being transmit ted
to the gear lever.
Three-spoke sports steering wheel with gearshift switches Three-spoke sports steering wheel with gearshift paddles Gear selector for PDKGear lever for six-speed gearbox
Hill-start assist.
Standard for manual and Porsche
Doppelkupplung (PDK) transmis-
sions it assists the driver in
making a comfortable, smooth
and roll-free start on an incline.
The system detects you have
braked to a halt on an incline.

Provided a gear is engaged, the
brake pressure is maintained
approximately t wo seconds once
the footbrake is released. The
vehicle is therefore temporarily
prevented from rolling backwards.
Brake pressure is reduced if
sufficient revs have been gener -
ated depressing the accelerator
pedal (for manual transmission,
the accelerator pedal is de-
pressed and the clutch engaged).

· 50 ·· 51 ·
Boxster and Boxster S
Suspension.
The suspension of the Boxster
models has been tuned to match
the high performance of the
engines.
Light weight coil- over McPherson
struts are combined with lateral
control arms to ensure excellent
driving dynamics and safet y on
all road surfaces. The axle kine-matics are designed for high
performance, as is the generous
wheel track. Light weight con
-
struction throughout keeps the
overall weight and unsprung
masses low, with almost all mov -
ing parts made from aluminium.
The mid-engine design, in com -
bination with the complex chassis
technology, results in minimum
roll and pitch movements on
cornering, braking and accel -
eration.
The chassis of the Boxster
models ensures high safet y
reserves irrespective of load,
and easily controllable load
transfer when cornering. Corner -
ing stabilit y is exemplary, even
in high-speed bends. The same
applies to straight-line stabilit y.
Steering.
What use is a perfect suspension
setup without perfectly tuned
steering? For Porsche, this would
be inconceivable. The solution
is a steering system which is as
precise and immediate as the
chassis itself and, thanks to the
power assistance, steering ef fort
is reduced to a comfortable
level. Around the straight-ahead
position, such as during motor -
way driving, the ratio is less
direct but with no loss of agilit y
or feedback.
Boxster | Chassis
The greater the steering angle,
the more direct the steering
ratio. This is particularly notice-
able when turning tight corners
or parking. The car has a turning
circle of just 11.1 m.
Front axle with McPherson struts and lateral control arms (Boxster S)
Rear axle with McPherson struts and lateral control arms (Boxster S)

· 52 ·· 53 ·
Wheels.
A range of sophisticated wheels
ensures both models deliver
exceptional driving performance,
without compromising on ride
comfort. The Boxster is fit ted with
17-inch wheels in an open five-
spoke design, and the Boxster S
has 18-inch wheels with a
dynamic sport y look. Wheels up
to 19 inches are available for both
models on request. All available
wheels are equipped with anti-
theft protection. A selection of
alternative wheels is featured
on page 108.
Specifically for the cold season,
winter t yres and snow chains
are available from the Porsche
Tequipment accessory range.
Tyre Pressure Monitoring
(TPM).
The optional Tyre Pressure Moni -
toring (TPM) sends warnings to
the on -board computer’s display
screen in the event of low t yre
pressure.

The driver can check the pres -
sure in all four t yres via the instrument cluster. The system
updates quickly and reliably

each time the engine is started, whenever the t yre pressures
are corrected or a wheel is
changed – ensuring a high degree
of comfort and safet y.
Boxster | Chassis
Boxster with 19-inch Carrera Sport wheel and Boxster S with 19-inch Carrera S II wheel
18 - inch Boxster S II wheel
17- inch Boxster III wheel