Camshaft question

Airstream65 said

Not sure, I haven’t put a light on it yet, because it has a fluid dampened balancer, so I want to determine if marks are correct (?). I have played with the timing just by advancing and retarding , then driving, I know that isn’t correct, but just a quick thing! The distributor has been re curved and the vacuum advance is not hooked to a vacuum line, so I need to figure out where to start with all of this!

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Yeah, butt-o-meter timing can tell You if total timing was a good bit off, plus or minus. To get the thing dialed in tho', well, You gotta do it right. You seem to know where to start here, get or make a TDC stop & verify the marks, get Your baseline readings & go. Most SBMs end up in the 34-36 total timing range, best idle timing depends on the combo, everything from 12° to locked-out at the total timing. It would be helpful to have actual cam specs, to know what You're workin' with.
Occasionally a cam/intake combo will cause a surge at certain part-throttle rpms, that may or may not be the case, otherwise it is usually;
1) lean condition
2) unstable fuel level or pressure
3) excessive timing at part throttle
Get Your baseline numbers & let Us know.
Also, setting idle timing by the vacuum gauge can work, but doesn't always give You the ideal. I've seen it bite people who "lived" by that method.