An intake manifold unit for fuel injection internal combustion engines

摘要

The cavity (3) of an intake manifold (1) communicates with each outlet (5) of the manifold and each outlet (5) leads to a cylinder of the engine through a first duct (7) and a second duct (8) which is longer than the first duct (7) and is in parallel therewith. Below a predetermined threshold value of the rate of revolution of the engine, the first duct (7) is obstructed by an obturator (17) with a face seal which cooperates with a flat sealing surface (21) constituted by a surface which defines the cavity (3) and in which the main duct (7) opens, the surface constituting part of the surface which connects two elements forming the body of the manifold.