pushrod's to long now? wtf!

Well before i called it a nite i did some checking on my pushrod lenght & from what i can tell it seems they need to be roughly .275 shorter than the stockers sound about rite? Man whats weird is ive used this same stock valve train on other LA motors with hydro cams & no problms what so ever. Wonder if isky is usen a "fatter" base lobe? would also make sence to. Any one got a part# for a ball & cup push rod .275 shorter than stock? thanks guys had to try.:hello2: