Thread: What would cause this lifter failure (pics attached)

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I started tearing down my SBC 350 to change out the cam, and I found 2 lifters with (I think significant) damage. They were on the front driver cylinder exhaust, and rear driver cylinder intake.

I have had problems with this bank before with roller tip rockers. What happened before is that the rockers had become very loose to the valve stem tip, slightly deforming them (yes these 2 cylinders). I switched to full roller rockers to replace the damaged rockers, thinking that they were simply way out of adjustment. What I am thinking now is that the lifters were collapsed or not pumping up, which caused the looseness originally. What I am worried about is if the oil FEED in this area is blocked, which is why the lifters did not pump up. HOWEVER when I used a tool in the dist hole after I put the rollers in, I DID get oil at EVERY rocker. Many I'm a bit confused and frustrated.

Both lifters are pretty badly cupped, and chewed up on the outer edge. The worse of the 2 had a discolored roller rocker. I suspect the color change was from excessive heat. I did not notice anything at all unusual (else) about the rockers, pushrods, valve stem tips, or anything else I could see.

I have my thoughts, but I would like to know if anyone has seen this type of failure and what causes it? Also is the discolored lifter related? If the cam and lifters are toast (likely), are there other potentially damaged parts?

Thanks in advance.