[screamingchief]

That happened because of those Comp Cams pushrod guideplates...

That is a fairly well known issue to some of us long time pontiac folks.

They just dont align the pushrod tip to the rocker arm cup very well @ all,the end result is they bind the valvetrain up,as that uneven alignment tends to inturn cause uneven contact with the tip of the valve,and that tends to break stuff as SOP.

Put some OE guideplates on there,and that'll almost certainly never happen again.

That or you gotta cut the CC guideplates in half leaving a little room between the halves so you can align the pushrods better,and then you just weld the guideplates halves back together after everything is lined up properly.

FWIW

Bret P.