Intake system for internal combustion engines

摘要

Internal combustion engine having a primary and a secondary intake passage for each cylinder, the passages opening to the combustion chamber through a common intake port having an intake valve. A substantially radially extending partition plate is disposed at the intake port so as to separate the two passages one from the other when the intake valve is closed. The primary intake passage has a centroid in a cross-section at the intake port and is so located that a line passing through the centroid and the center of the intake port intersects a projection of the cylinder bore at a point of intersection and makes an angle of 50 DEG to 80 DEG with a tangential line of the projection of the cylinder bore at the point of intersection.