Old hat...

First, I am not lookin up specs for that cam when all you provided was a part number. Secondly, 9.9:1 is NOT pump gas friendly with iron heads, I don't care what some forum genius says. Unless you have a camshaft that does not allow complete cylinder filling because of a late intake valve event, you will have trouble on pump gas.

I would begin as AJ suggested and run a compression test. Post up your numbers. But remember, a compression test is not the end all be all, because as engine RPM increases, guess what? So does cylinder pressure. So by the starter, you may see 140-150, which is acceptable, but who knows where it is in the RPM curve of the engine? This is why fancy formulas and such are sometimes useless as tits on a boarhog.

Sometimes you simply have to get dirty and actually TUNE the thing. I suspect that's what you are going to have to do here. Let us know what those compression test numbers are and we can go from there.