Another critical issue with installed height is the total lift available. If you use the wrong installed height the valves may not be able to open as much as the cam manufacturer intended. This can cause coil bind, and broken valve springs, bent pushrods etc. Part of your spring specs will list a maximum lift value. Make sure you dont exceed this value especially when going from 1.6 to 1.7 ratio rockers. A cam at 0.50" lift at 1.6:1 rocker ratio will have 0.5313" lift with 1.7" rockers. If the springs only had 0.525" max lift you will have problems.
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Frank W
90 5.0 LX coupe Daily driver. Silencer removed, K&N filter. Flexalite fan, 3 core radiator. FMS flywheel and Clutch Finally rebuilt T-5.
74 Chevy Laguna Type S-3 305 apart in garage, getting a 454 to put next to it
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