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isn't the ideas to have the rocker tip center on the valve stem hence the needs for the shim when you shave the head too much?



How does shaving the head effect valve to rocker relationship?... Valve stem height effects it & there is a specicfied height for them... The distance from the C/L of the rocker pivot to the point it contacts the valve effects it... But milling the head or deck surface doesn't... Again I'll post this picture which shows what shimming the rocker shaft effectively does...