Patent attributes
A method for operating and engine having a cylinder with at least an intake and exhaust valve, comprising of performing a combustion cycle in the cylinder in which exhaust valve closing occurs after intake valve opening thereby creating valve overlap, boosting intake air above exhaust pressure, where said boosted intake air is inducted into said cylinder while said intake valve is open and at least a first portion of said inducted boosted intake air flows past the exhaust valve with both said intake and exhaust valves are open during said overlap, directly injecting fuel to said cylinder that is combusted in said cylinder, where a beginning of said fuel injection occurs after said exhaust valve closing and said directly injected fuel is mixed with at least a second portion of said inducted boosted intake air, and combusting said mixture at a rich air-fuel ratio.