OK fellas,
Here it is again. 64 225. 1bbl carb (tried 3, all the same). Fresh rebuild. Cam properly broke in. Runs fine off idle, and on fast idle, but a little rough. Cam is crane s-264. Intake and exh. lift-.434. 265 deg. duration, 42 deg. overlap. Have the hot lash set at .018 int. .022 exh. Have messed with timing all over the place. Tried vacuum advance, no vacuum advance, manifold vac, ported vac. WHAT AM I MISSING???? Also, no vacuum leaks, that I can find, but vacuum is at 13 steady cruising, and will drop to around 18 on a decel. Kinda low, but maybe the cam is causing this???
Please help.

Tim

Did you degree the cam? Retarded cam timing will do this.
DD

A leak in the exhaust, even the slightest will cause rough idle. It is a problem I've been dealing with. my manifold cracked, so I got that fixed. It ran fine, for a while until the exhaust dopped. It got a few leaks, then it ran fine when I patched those. Then of course I fixed it after a few. That wasn't very smart. Guess what? Same thing. But it ran fine with no leaks.