| 摘要 |
A first camshaft (24) operates the exhaust valves (18) and a first intake valve (12) for each cylinder (8), and a second camshaft (38) operates the second intake valve per cylinder (14), the second camshaft further having a phase adjuster (62) for adjusting the timing of the second camshaft (38) relative to the first camshaft (24). Both the exhaust valves and the first intake valve are actuated by rocker arms (30),(36), for providing a short and light-weight first intake valve rocker (36) having a high maximum operational speed capability and low friction. The first camshaft (24) is located above the rockers, the cam followers are located generally in the middle of the rockers (30),(36), and the rocker mounts (33),(35) are located on the inboard ends of the rockers, providing rockers that have both light-weight and a small pivot angle for providing low valve stem to rocker friction.
|
