摘要 |
The present invention provides in all aspects an intake manifold (10) for an internal combustion engine having a plenum (22) to be filled with combustible charge and inlet passage means (27) serving in use of the manifold (10) to connect the plenum (22, 23) with a cylinder (11 to 18) of the engine. In a first aspect of the invention the intake manifold has first and second plena (22, 23) and the inlet passage means (27) connect each plenum (22, 23) with a cylinder (11 to 18) of the engine such that combustion chamber means of the engine which fire consecutively are respectively supplied with combustible charge from a different plenum (22, 23). In a second aspect of the invention the manifold (10) has inlet passage means (27) comprising wall means (46) dividing at least a part of the inlet passage means (27) into a plurality of paths (44, 45) for fluid flow, and valve means (47) operable to open and close at least one of said paths (44, 45). In a third aspect, the invention provides an inlet manifold having a first and second plena (68, 69) each supplying a different plurality of cylinders of an engine and plena connecting means (60, 61, 62) operable to connect first (68) and second (69) plena to allow all of the cylinders (71 to 78) of the engine (90) to receive charge from both plena (68, 69) and to allow the resonant frequency of the intake manifold to be altered. |