Cylinder head intake system

摘要

An internal combustion engine cylinder head includes a pent roof (15) closing off a top of an engine cylinder (14) and first and second inclined surfaces (15a, 15b) intersecting an apex region (15c) of the pent roof. First and second air intake ports (20, 22) are formed in the pent roof surfaces and about respective first and second spiral axes (S1, S2) having respective radii (R1, R2, etc.) that change in magnitude and elevation as each air intake port approaches respective port entrances (20a, 22a) to the cylinder in a manner to provide air flows with in-cylinder air swirl in the same direction about the longitudinal axis of the cylinder.