[eschaider]

zzmac, I'd bet you dollars to donuts when your carb was rebuilt they put in new power valves just to cover all the replaceable componentry bases. I'll also bet they put in 6.5 or higher vacuum point opening power valve. If they did, that means your power valve(s) are open at idle.

To correct the rich idle mixture caused by the wrong power valves it becomes necessary to lean out other fuel delivery circuits which is why your engine stumbles. Stumbling is almost always (99% of the time?) inadequate fuel delivery in the tip in / off idle behavior of the engine.

Take another look at post #13. Your fix could easily be as simple as installing a 3.5 or 2.5 power valve and correcting your idle mixture. Just for grins why not measure your idle vacuum. I would bet you are down in the 6 to 7 inches of vacuum range at idle. If you are, you need a power valve that is essentially ½ that number.


Ed