Why did you tear in to it? was it making noise? Just wondering how you came to find out the lobe was bad..

 

i had one go bad on a sbc. it would run great for a few minutes. would start leaning out after a few minutes of driving and running like ****. changed intake gaskets, checked timing and distributor, jetted carb, nothing worked. i didn't get any ticking or weird noises that i remember.
pulled the cam, thinking i had too much dynamic compression(11:1 static, 8.4 dcr) and when it got hot started doing stupid ****, to put in a bigger one. thats when i saw a couple of the lobes were wiped.

 

Both times I had ticking from the block which would come and go. First time I had a lifter seized in the lifter bore, and damaged the matching lobe. I replaced the plastic lifter trays after that with an LS1 rev-kit.

The next time it happened I heard a rattle and took the heads off, found that the aluminum on one piece of the rev-kit had fractured and was rocking against the bottom of the head. The affected lobe was on another lifter though. Not sure what caused the lobe wear. Never sent it back to Comp because I didn't think they'd do anything for me.