intake-charge back, out from the cylinder, polluting the intake manifold with exhaust.

Continuous versus discrete

Early variable valve timing systems used discrete (stepped) adjustment. For example, one timing would be used below 3500 rpm and another used above 3500 rpm.

More advanced variable valve timing systems offer continuous (infinite) adjustment of the valve timing. Therefore, the timing can be optimized to suit all engine speeds and conditions.

Cam phasing versus variable duration

The simplest

1.Previous
3.Next