Problem installing rockers

[Carmelo C]

350 5.7L , I recently changed one head, I used the same push rods and rockers. When I tightened down the nuts on the studs I reached zero lash before the stud cleared the top of the nut. Normally there’s about 1/4 inch of thread sticking out the top of the nut. What am I missing or what could be the cause? Stud height is the same on old head and new head, the only thing I’m thinking is the Spring tension on the valve. The lifters are sitting in the correct spot

[34_40]

Welcome to the site. Do you still have the old head? I'd be wondering if the "thickness" of the heads are the same.?.? Did you compare P.N.'s ?? Or did you compare the heads side by side at all??

[rspears]

Welcome to the site. Do you still have the old head? I'd be wondering if the "thickness" of the heads are the same.?.? Did you compare P.N.'s ?? Or did you compare the heads side by side at all??

Yep, I was thinking the same thing. While the stud height is the same head to head I'm betting that the new head is shorter from that base of the stud pad to the machined surface of the head making your pushrods too long. Pretty sure you've got two different head designs, not that it won't work if you set it up right.

And welcome! Let us know what you find.

[Carmelo C]

Hey guys, Rspears you hit the nail on the head, although it was the same ***906 head it was the platform the stud sits on. It must have been altered at some point in its life. I removed and replaced the studs and runs great now. Thanks again