Porsche 911 Carrera 4 Brochure & Specs page 21

VarioCam Plus System. This two-in-one engine concept
seamlessly adapts in response
VarioCam Plus combines variable to driver input. The result: instant
valve timing with two-stage lift acceleration and extremely
on the inlet side. This results in smooth running.
smoother running, better fuel
economy and lower exhaust The variation in intake timing is
emissions. As well as greater top- steplessly controlled by means
end power and low-end torque. of an electro-hydraulic 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 torques
and maximum output.
Lightweight construction. fully integrating the camshaft
bearings into the cylinder heads.
The advantages of an alloy engine
are its low weight and reduced Fuel economy has been further
fuel consumption. improved by the effectively
designed oil supply system and
The intelligent engine design saves the low mechanical friction of
even more weight, for example, by the engine.
The 911 |
Engine
911 Carrera 4S Cabriolet