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Originally Posted by Mike Woodman
Maybe I was reluctant to degree the cam cause I was foggy about it. After some thought and having read the responses I agree that it makes sense to do it and be sure.
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I had bought a cam for a Pontiac 455 I was building from an outfit called Columbus Auto Parts or Columbus Racing Products- something like that. I still have their catalog from like '88.
Anyway, I got the camshaft along w/a pile of other parts and proceeded to assemble the short block. I wasn't going to degree the cam, thought "why bother". Then a friend of mine who happened to come by said I ought to take a look, he thought it looked like more lift than the card said (called for around 0.480"), so to shut him up, I real quick put my mag base dial indicator on it, and sure enough there was more lift- but only a little.
Lucky guess on his part, but this puzzled me enough that I went ahead and degreed the intake and exhaust lobes of #1 and sure as hell, the cam was WAY different than what was in the catalog: It was ground on a 108 LSA, not a 112, it had 10° more duration and the lift was about 0.015" more.
After some deliberation (and since I hadn't built the heads yet) I decided to use the cam anyway (installed advanced), and to go ahead and port the heads instead of installing them as-is. I wasn't disappointed w/all the extra work, the engine ran very good for an all iron 455 w/a Performer intake- but if I hadn't known the difference was there I'd have been in for a tuning nightmare trying to make sense of the lower idle vacuum, the lope and such!
So if you can justify the time, like it seems you can, I agree that there's no good reason NOT to degree the cam.