variable valve timing

[dale]

How does the variable valve timing work on the 2008 3.2 S 80 What adjusts it and how is it adjusted in the engine?

[jimmy57]

The 3.2 has intake cam variable valve timing and 2 level intake vale opening.
Below around 3000 rpm the intake valves are only lifted off seat 3.6 mm and throttle opening and cam timing control engine speed.
Above that rpm the valve opening is 10mm and throttle is the engine speed control with some cam timing changes primarily for improved torque and lowered emissions.
The intake is also 3 stage design with two dampers to alter plenum+runner volumes for optimal pressure wave tuning.
The intake cam has a hub with radial vanes working inside pie slice shaped chambers. Oil pressure control in the chamber split in two by the radial vanes controls where the cam is in its travel range. The ECM controls an on-off pulse to the oil control valve. The valve sends oil to one side of vane when not powered and to the other side of vane when powered.
The cam position sensor is monitored relative to crankshaft position in order for ECM to know what signal will get cam to desired position.