· 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.
· 38 ·· 39 ·
Exhaust system.
The exhaust system – with t win
tailpipes on the Boxster S – is
made of stainless steel. Until it
converges in the connecting tube,
the exhaust gas is channelled
through t wo separate tracts and,
thanks to separate exhaust gas cleaning systems, the exhaust
gas can flow more freely – for
increased power and torque.
The stereo lambda control
circuitry controls and monitors
each cylinder bank separately.
For each exhaust tract, four
corresponding oxygen sensors regulate the composition of the
exhaust gas and monitor the con
-
version of pollutants in the cata -
ly tic converters.
A sports exhaust system – for a
more resonant sound – is avail -
able as an option for each of the
Boxster models.
Boxster | Drive
Servicing.
Every Porsche is designed with
durabilit y in mind. On the Boxster
models, this is reflected in the
lengthy service intervals. The alternator, power steering
pump and the air- conditioning
compressor are all driven by a
single self-adjusting belt. The
drive chains on the camshafts
and intermediate shaf ts do not
normally require servicing. With the sole exception of the
spark plugs, the ignition system
is also maintenance-free.
So your Boxster remains where
it belongs for as long as possible:
on the road.
Boxster S exhaust system
Boxster S twin tailpipe
Boxster tailpipe
