| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain an intake charging efficiency of an engine high in spite of dimensional change by manufacturing tolerance and a secular change of an exhaust pipe. SOLUTION: Exhaust pipes from each cylinder of an engine 1 are collected to two exhaust passages 52 and the like to constitute a dual exhaust system. The engine 1 is provided with a variable valve timing mechanism 10 which varies an intake valve open/close timing of each cylinder. A control circuit 30 controls the variable valve timing mechanism 10 based on an engine intake air amount input from an air flow meter 15 provided to an intake passage 13, and an valve timing of the engine is changed so that the time when a negative pressure wave generated by an exhaust pulse is attained to an exhaust port corresponds to a valve overlap period of an engine intake/exhaust valve.</p> |
