Patent ID: 8100115

Claim:
A method for operating a supercharged spark ignition engine ( 1 ) including an intake duct ( 11 ) with a charger ( 14 ) and at least one intake valve for controlling the flow ( 2 ) of combustion air to the spark ignition engine ( 1 ), and an exhaust duct ( 12 ) for discharging exhaust gas from the spark ignition engine ( 1 ), the engine having a geometric compression ratio of at least 10, said method comprising the steps of: closing during full load engine operation the at least one intake valve of the spark ignition engine ( 1 ) very early or very late so as to reduce the volumetric compression ratio during full load engine operation, and re-circulating exhaust gas from the exhaust duct ( 12 ) to the combustion air flow ( 2 ) the closing time of the at least one intake valve being controlled as a function of the engine operating point and the load demand.