Exhaust manifold for internal combusion engine

摘要

An exhaust manifold (1,101) connected to exhaust ports of at least three straightly arranged cylinders (#1,#3,#5) of an internal combustion engine, comprising: a primary exhaust pipe (111,112,113) extending from the foremost cylinder (#1) of the cylinders in a rearward direction of the engine along a direction of the straight arrangement of the cylinders; and a plurality of secondary exhaust pipes (115,116) extending from the other cylinders (#3,#5) except for the foremost cylinder (#1) to the primary exhaust pipe, wherein each secondary exhaust pipes comprises an intermediate portion (115b,116c) winding around to an outer periphery of the primary exhaust pipe.