508 or 509 Purple Shaft cam

csx452 said

Yes, it is a damn goodun and I was running 410s before pulling the engine. I'm not worried about .001". I just want to be able to properly degree the cam. I do appreciate the info I've gotten on here and I come here for advice because of the reputable people on here.

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Just go by the part number. It is P4120233. .508/.508 248.5* @ .050 on a 108 LSA with 76* overlap. I think the MP Performance book even has all of the valve timing events as well, but you can degree it regardless. Just keep in mind that huge amount of overlap. That is what bleeds off cylinder pressure. That's the reason you should run 10.5 minimum compression.