| 摘要 |
<p>PURPOSE:To obtain activity of a catalyst converter and suppress its heat deterioration by controlling a valve timing mechanism which can vary the valve timing of an intake valve to delay the closing timing of the intake valve at the times of a low load condition in a low rotation range and a high load condition in a high rotation range of an engine. CONSTITUTION:A V type 6-cylinder engine E having a mechanical type supercharger, is provided with an exhaust passage comprising exhaust passages 23A, 23B of left and right banks extending from exhaust manifolds 22A, 22B of the left and right banks 1A, 1B and a confluent exhaust pipe 24. Catalyst converters 15A, 15B are provided in the respective exhaust passages 23A, 23B. A valve timing variation mechanism 30 is arranged so as to vary valve timing of intake valves 3 at the banks 1A, 1B. In this case, the valve timing variation mechanism 30 is so controlled as to delay the closing timing of the intake valve at the time of at least a low load condition in a low rotation range and a high load condition in a high rotation range of an engine.</p> |
