Load control of a spare ignited engine without throttling and method of operation

摘要

A spark ignited engine and method of its operation in which throttling losses are substantially eliminated has two intake manifolds operating at different charge air density levels. Suitable valves, upstream of conventional cylinder intake valves, are controlled to supply each of the cylinders with charge air from one or the other manifold. At high loads under operation of a controller all of the cylinders are supplied from the high density charge air manifold and at low loads all of the cylinders are supplied from the low density charge air manifold. At intermediate loads the controller supplies an appropriate number of cylinders from the high density manifold and the remaining cylinders from the low density manifold.