Hi all, Just a query. When you install after market camshafts, what sort of changes need to be made? If I'm right in saying, aftermarket cams have larger cam lobes yeah? This giving a larger intake draw. Other than a decent map and other supporting mods and that, how would stop the pistons crashing into them as they will be holding the valves open further? Would you retard the valve timing by a certain amount of degrees or teeth? or am I wrong?