Quote:
|
I've been told if someone swaps late SC heads with early SC heads, 964 or 20/21 cams are a must.
|
I'm not sure if I would come to the same conclusion since both the "early" ('78 and '79) SC's and the '80's and later SC's had about the same HP. So just swapping the heads alone can't have that big of a difference (all other things being equal). I think that the conclusion would be that if you are going to use the 20/21 cams with CIS or possibly unported late heads, you should specificy a wide cam lobe angle to minimize the overlap. If you have early style heads or 3.2 heads and you are running carbs, then by all means go for a narrower cam lobe angle, but keep in mind that the overlap will still hurt your low RPM performance some. But your peak HP will most likely be a little better.