[davepl]

This isn't a tuning issue. You can set dwell and mixture all day, not going to fix it.

If people would set their engines up mechanically as their were originally, they'd be a lot further ahead. But people figure they know better than GM and they start hooking vacuum advance up to manifold vacuum, stuff like that, without really knowing why.

If you fix the mechanical problems (like vacuum leaks) and set the timing to 12 degrees BTDC, idle to 750, then the mixtures two turns out, the thing should run pretty well. If it doesn't, then as I say, you've got a vacuum leak or something.