In order to make cam clearance maintenance-free, and achieve operation sound reduction, hydraulic lash adjusters are adopted to the SR20 engine.
However, when aiming at high rotation and a high output by engine modification, it is important to improve the reliability of head parts and to make valve drive correct as the cam profile. It is necessary to eliminate the function of lthe ash adjuster.
Tomei have adopted a solid pivot system to enable cam clearance adjustment, while keeping the total height of pivot of each cylinder fixed. Thereby, it is possible to build a much more precise head system in a shorter time compared to others. Moreover, improvement in reliability and the low price were realized at the same time by having reduced the number of parts.