Tomei's solid pivot kit has been designed and tested for high RPM and high horsepower applications. Mitsubishi chose to use the lash adjuster (hydraulic system) for the 4G63 cylinder head for mass production efficiency, maintenance free and quieter operation. The best way to get more power from the 4G63 engine is to convert it to the solid system which is by far more superior in allowing running more aggressive camshaft profiles. The Solid conversion helps with more efficient opening and closing of the valves and therefore helps improve response throughout higher RPM ranges. This product uses internal shims to adjust the height. Designed to be used in conjunction with other solid conversion upgrade products from Tomei Powered for the 4G63.