Method and apparatus for calculating minimum valve lift for internal combustion engines

An engine control system for controlling valve lift of an intake valve for a cylinder of an internal combustion engine, comprising:

• a controller that stores a first desired pressure ratio (Pcyl/Pint) for induction pumping losses, that calculates maximum cylinder demand, and that calculates intake valve lift by matching an effective flow capacity through at least one intake valve of said engine to said maximum cylinder demand;
• and
• a valve actuator that adjusts said intake valve based on said calculated valve lift.

A engine control system for controlling valve lift of an exhaust valve for a cylinder of an internal combustion engine, comprising:

• a controller that stores a second desired pressure ratio (Pexh/Pcyl) for exhaust pumping losses, that calculates maximum cylinder demand, and that calculates exhaust valve lift by matching an effective flow capacity through at least one exhaust valve of said engine to said maximum cylinder demand;
• and
• an actuator that adjusts said exhaust valve based on said calculated exhaust valve lift.