so i recently rebuilt an engine for my 72 el camino. i bought a pair of World Sportsman II Cast Iron cylinder heads. during assembly i noticed that with the stock pushrods and rocker arms, the bottom of the rocker arm was touching the edge of the valve spring retainer. i ended up getting some oversize pushrods on the advice of a friend, and when i assembled it and adjusted the valves, it seemed to barely clear the retainer which i figured should work. i still used the stock rocker arms with the oversized pushrods. so then i finished my engine, started it up, drove it around for about 150 miles, and everything was working pretty good (except for some gearing issues, but thats a different story) but then rather spontaneously i developed a slight tapping noise in my valve cover which in a matter of minutes turned into a hardcore rattling and banging so i turned off my engine, pulled the valve cover, and my rocker arm fell out. i had sheered the stud off right below the end of the threads. the stud looks like it was cut with a laser. i pulled all my studs and rocker arms and realized that i had signifigant wear on nearly all the studs and some of the rocker arms. the wear seemed to be in random locations, sometimes facing towards the valve, sometimes facing towards the front of the car, etc. at this point i noticed i had tiny wear spots on the part of the rocker arm that is right above the retainer. upon further inspection most of the rocker arms had this wear spot, and nearly all my valve spring retainers had a tiny contact spot, so obviously my rocker arms are still hitting the valve retainers. the wear to the valve spring retainers is insignifigant i hope, when i rub my finger over it i feel the slightest little burr, so i left those in the car. should i be concerned about that tiny little nick in the retainers? does anyone know what i should do to get my rocker arms to clear the valve retainers?? and also, does anyone know if my rocker arms contacting my valve retainer would cause the extensive wear (and destruction) i have on my studs and rocker arms?? thanks for your time

welcome..
were these the stock stamped steel rocker arms?
if so, that's your problem.
the slots where the stud goes thru the rocker is too short for a cam that is much bigger than stock, which means that it will hit the stud on either the front or rear of the slot at full travel. this explains the broken stud.
they also don't have the right shape to clear the larger aftermarket spring retainers.
aftermarket roller rocker arms are designed to clear larger than stock spring retainers, and have a slot that would take an awful lot of lift to cause any issues.

thanks for the help ill give that a shot. would i want to go back to the stock sized pushrods when i get the rocker arms that will work correctly? and should i be keeping an eye out for other things, such as cam or lifter damage? i figure changing the oil is a must

you may need to go to roller rockers. is it a stock build? have large diameter valve springs?

IMO you need to get it fixed before any more miles. Really unfortunate things happen to engines that have interference around the retainers.

Do you have screw-in studs and guideplates? World used to have problems with the alignment of the pushrod holes in the heads. caused the rockers to ride off the sides of the valves but probably wouldn't cause the problem you're seeing.

unfold a paper clip, it will serve as a gauge. Should be able to slide it between the rocker and the retainer anyplace in the lift cycle.

on the pushrods, check for a wear pattern on the valve tips. it should be more or less centered, not coming close to the edge either on the intake or exhaust side of the head.

i do have screw in studs and guide plates. i already pulled all the old studs and rocker arms, so im definitely not taking it for a ride anywhere until this is all fixed. the valve retainer diameter is bigger for sure, i dont know the actual measurement but just by eyeballing between this head, and the heads i took off this engine originally, they are bigger. im gonna try the roller rocker arms with new studs idea, but does anyone have a brand theyd suggest? i was looking at rocker arms yesterday and theres only about 999999x brands. the paper clip idea sounds good, i dont think i couldve fit a paper clip between the rocker arm and valve retainer with those stamped steel rocker arms. the wear patter looks normal on some valves, but there are several as well where the wear seemed to go off the edge of the valve on the exhaust side. maybe cause of the longer pushrods? im still wondering too if with the new rocker arms, should i go back to stock pushrods? seems like id want to... and because my rocker arms were not rolling like they should, seems like thatd put pressure back down on the lifter and camshaft. should i be worried about flattened lobes? or hopefully did the little piston in the lifter take up that slack?