What would cause this?

[B.A.D Performance]

What would cause this? Lack of lubrication or weak valve springs? There was valve to piston contact. The motor had right at 300k miles and ran comp 910s shimmed. Other mods are in the Sig only difference the turbo was a 38r at the time

 

[backwoodsboy]

Lack of lubrication would be my guess.
Low seat pressure typically won't cause pitting on the lifter and cam. Too high of seat pressure or coil bind will.

 

[Crowerstroke02]

the driver hahahahahaha:lookaround:

 

[Tom S]

Seems to me that would happen when two parts were pounded together. Is that on the lift side of the lobe or the other side.

 

[B.A.D Performance]

Thats a good question. Never thought to look. I do remember some of the valve stems were mushroomed out from the rocker arm beating on them. Ill have to check and see what of the cam its on

 

[Hotrodtractor]

It looks like the case hardening was worn through on the camshaft and once that is gone... its all soft. That soft area doesn't wear very well and as you can see it gets ate up. That pitting is actually the material galling up with lack of lubrication and a soft cam. One of those lifter rollers siezed up somehow and basically turned it into a rounded tappet and let it get ate up by the soft cam. Time for a new cam and all new lifters.