The role of rocker arm in combustion engine

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Rocker arms and pushrods are the essential components for performance engine building. The rocker arms redirect the upward motion of the lifters and pushrods into the downward motion required to open the valves.

Using a higher rocker ratio produces more valve lift to gain extra power under the same cam lobe profile. If the rocker ratio is increased, the rate at which the valve opens is faster and hence the effective duration of the camshaft becomes longer. Please remember that if you change the rocker arm, you have to reconsider the camshaft profile (vice versa).

Measurement data

To install a new rocker arm, please make sure that the valve springs have enough clearance between the coils. Otherwise, the springs may bind. In addition, please ensure that the valve keeper doesn’t bombard the top of the valve guide.