Spark ignition engine exhaust system

摘要

Exhaust system for a spark ignition engine includes exhaust pipes (16) connected to engine exhaust manifolds and a catalytic converter (18) connected at one end to the exhaust pipe (20). An exhaust filter (30) is positioned upstream of the catalytic converter and a bypass control mechanism (56) directs gas towards and away from the exhaust filter. The filter condenses hydrocarbons, which are evaporated by passing exhaust gases to heat the filter in a second circuit.