[HeavyHauler]

Originally Posted by 68 P.O.S.

Sounds like you have a couple potential issues. First things first, timing. If your timing isn't correct, everything else will be off as well. GM engineers found Chevy engines run best at 36 degrees total timing, 38 at higher elevations. Set your total timing accordingly and then move on to your carb. If you plan on sticking with that carb, your best bet is to clean it out real well and throw a rebuild kit at it. Then set the float levels to specs and regulate the fuel pressure to 5.5 psi to prevent flooding. Next, put a heat insulating gasket under it, to prevent fuel percolation, which causes the hard starting after warm up you're reporting. You also have to set the transition slots in the throttle bores to be a square to ensure it's only idling on the idle circuit. What is your idle rpm set at, or the range its bouncing around at? I'm wondering if it's set too high and allowing the mechanical advance to dip in n out? Idle should be 750 rpm for auto and 600 (I believe) for manual. Which distributor are you running, original points or HEI? I agree with Caddylackn, make sure the distributor advance weights are well lubed. After messing with the carb, hook the vac advance up to manifold vacuum. Then after you get it running well, use a vacuum gauge connected to manifold vac to set the idle mixture screws for highest vacuum. Hopefully this fixes your issue and the throttle shafts are fine. If you don't already have it, download a copy of the Edelbrock instructions. All you need to know is in there as well.

I checked timing and initial is at 12 BTDC and 36 total.