[Formulajones]

Originally Posted by Bill S

Took my 6X heads to very reputable engine machine shop / builder last weekend. Had him check the heads over and flow test a intake port, then had him test the valve springs. They all read very low at install height (1.700"), about 70-80 !

Thinking that may have been a contributor to the wear issue. Evidence included beat up spring shims, valve end burrs, and a couple of seats in the heads needing a touchup. I have read about many problems which arise from worn / incorrect springs.

I did a Pontiac engine a couple years ago that only had a couple thousand miles on it from a previous build, and upon tear down, the valves springs were like yours. Lucky to have 80 lbs. on the seats, and it was chewing into the bottom of the retainers, and the locks were taking a beating. There was a good chance after a while that it will drop a valve like that. Probably lucky the cam went flat first.

The valve bouncing on the seat as a result, and unable to control the valvetrain properly, with the lifter likely beating the lobes, is one possible reason for the cam failure.

I also believe the oil is another possible cause. The two combined looks like a good indication.