Abstract: An induction system for a multicylinder reciprocating internal combustion engine includes cylinder 8, cylinder head 10 having at least one intake poppet valve 12, and at least one exhaust poppet valve 14, with the induction system further including a crankcase ventilation system 26 for conducting gases from the crankcase of the engine to the cylinder head, and a PCV passage for introducing crankcase gases directly into at least one of the engine's intake ports 18. In the case wherein multiple intake valves and ports are used, PCV flow may be introduced through one port, with recirculated exhaust gas being introduced through a second intake port.

Abstract: A multicylinder reciprocating internal combustion engine with a dual induction system having at least one exhaust poppet valve and a single intake poppet valve for each cylinder, with the intake valve being located so as to control the flow of charge into the cylinder. Each intake port has a vertical wall dividing the port into primary and secondary passages, with the primary passages being oriented so as to cause rotational flow about the outermost portion of the cylinder, and with the secondary passages being oriented so as to cause flow directed about a radially inward portion of the cylinder. Low-speed and high-speed intake runners extend from an intake plenum to the primary and secondary intake port passages.