EXHAUST SYSTEM STRUCTURE OF ENGINE

摘要

PROBLEM TO BE SOLVED: To prevent a trouble in which exhaust gas passing through a turbocharger 2 becomes spiral flow and flow velocity distribution of the exhaust gas on the upstream end surface of catalyst 9 is biased when a curved part 7 exists in an exhaust passage on the direct upstream of the catalyst 9. SOLUTION: This exhaust system structure comprises a linear part 6 in which the exhaust gas flows as the spiral flow, the curved part 7 connecting to the linear part 6 that is curved about a shaft orthogonal to the linear part 6, and a diameter expanded part 8 extending from the curved part 7 to the upstream end surface of the catalyst 9. The curved part 8 has a flow dividing part 11 for dividing the flow of the exhaust gas and the bias of flow velocity distribution of the exhaust gas is reduced.