Porsche Cayman User Handbook Manual page 35

Two-stage resonance
intake manifold.
The intake manifold with
double-flow distributor pipe has
an adjustable flap that closes and
opens at defined engine speeds.
As a result of a two-stage
resonance effect, the air mass in
the intake manifold begins to
oscillate, which in turn generates
a turbocharging effect and
optimises induction. These two
effects combine to produce
higher torque at low engine
speeds, a flatter torque curve and
increased power output at high
engine speeds, while the acoustic
properties of the system are
second to none. A sound that is
typically Porsche.
VarioCam Plus.
VarioCam Plus combines variable
valve timing with two-stage lift
on the inlet side. This results in
smoother running, better fuel
economy and lower exhaust
emissions. 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 electrohydraulic rotary
vane adjuster at the head of the
corresponding camshaft.
To improve throttle response
during the warm-up phase,
VarioCam Plus selects high valve
lifts with retarded valve timing.
In the middle and low load ranges,
low valve lifts with advanced
timing reduce fuel consumption
and exhaust emissions. High valve
lifts generate high torque and
maximum output.
Cayman | Drive
VarioCam Plus
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