As a matter of fact, yes, there is lots of black smoke under hard acceleration. I thought it was because there is too much unburned fuel in the cylinders washing past the rings. I can smell gas when I change the oil.

I sprayed starting fluid around the base of the carb yesterday and there was no difference in the idle rpm. By vacuum leak do you mean to check the vacuum advance or something else? I have a gauge to check it with.

Thought that the flooding problem was due to the needle not seating in the valve correctly or being the wrong size and fuel is seeping past the valve when shut down. Why would the carb bleed down into the manifold flooding the engine when it's shut down?

Also, by the float level do you mean when the float is seated at the top of its stroke or the float drop? Thanks for your help