Engine exhaust system.

摘要

The invention relates to an internal combustion engine wherein an exhaust duct (16) is formed in the cylinder head, in good thermal contact with the engine coolant, and flow diverting valves (50, 52) are provided in the exhaust system to direct exhaust gases to flow through the exhaust duct (16) when the engine is cold in order to accelerate warm-up, the valves (50, 52) causing the duct (16) to be by-passed under normal operating conditions.