Engines

摘要

A spark ignited four stroke cycle internal combustion engine having variable volume combustion chamber, ignition means to provide an ignition point in said combustion chamber, a valve controlled inlet port communicating the combustion chamber with an air induction passage through which air flows to the engine. The induction passage including a wall shaped to direct at least part of the air flowing along said wall portion when the port is open in a generally helical path about the port axis and when the port is open, the air flowing is directed into the combustion chamber to establish therein a generally helical air flow. A fuel injector nozzle located to deliver fuel into the induction passage on the opposite side of the inlet port axis to said wall portion of the induction passage and on a trajectory through the port when open to form an ignitable fuel cloud at the ignition point.