ugh. valves are not nearly as important as springs and retainers. think about it, if u drop a valve in a zero tolerance motor, i dotn give a fuck what there made of, its gonna bend. have the stock valves relapped, have a 3 angle valve job anmd put in some dual valve springs and retaines. for the cost of that shit tho, put pistons and rods in the bottom end and get that dinky edelbrock kit and up the boost on that motha

on an other note, putting new valves into a head is pointless unless u have a valve job done.