Intake system for v-type engine

Abstract

Each cylinder bank of a V-type engine is provided with a plurality of cylinders which are not in sequence in firing order. A collecting intake passage is connected to each of the cylinders of both banks by way of independent intake passages which pass between the two banks and have the same effective channel length, and each of the independent intake passages is arranged so that it extends substantially perpendicularly and upwardly from a cylinder. Both collecting intake passages are arranged above one of the cylinder banks, and the collecting intake passage which is connected to a cylinder of the other cylinder bank is arranged on the independent intake passages connected to the other collecting intake passage. By doing so, overlapping of both collecting intake passages can be avoided and thus the height of the intake system can be reduced. The independent intake passages and the collecting intake passage which overlaps the former have a common wall. In one embodiment, each of the collecting intake passages is formed integrally with a high speed intake passage and a low speed intake passage. The vertical positions of the high speed intake passages for each bank are varied. The high speed rear side intake passage is connected to the underside of the low speed rear side intake passage. The low speed and high speed front side intake passages are connected to each other by way of a common side wall.