The issues you mention are somewhat "part of the breed" of Slabs, even with the "real" gas we had when the cars were new. Might dig out the factory insulator bag under the intake, if it's still there, for better air flow under the intake at all times (as the Performer RPM manifold does). If the carb is new or recent, might set the floats to slightly lower, but not much, which might help lessen any flow-over fuel.
The OTHER thing is to use about 2/3 throttle on any hot restart, being careful to reduce the throttle setting once the engine fires. Otherwise, the factory recommendation was 1/3 throttle, as I recall in the owner's manual.
IF you used the carb base gasket supplied with the car, it's NOT a good gasdket, to me, for anything other than sealing things up. The factory base gasket was about 3/8" thick with metal/hard plastic bushings in each mounting stud hole to limit compression of the gasket (so as to not crack the carb base by uneven torque situations). They can still be bought in Edelbrock and Holley brands, if not from NAPA or similar. I concur with the heat insulation properties of wood, although it might appear to be a good place for a fire (reflex action), but I have a drag racer friend who has used a wood insulator for years with no issues that I know of.
The air cleaner is not the issue with heat retention that it might appear to be. Any heat it might abso absorb will be above the carb and rise. It's that chunk of cast iron below the carb that radiates heat upward around the carb. Once the engine starts (and the fan clutch works as it should), there is plenty of air to get to the carb, even with the RV-2 compressor in the way, by observation.
Whatever issues we had back then are probably magnified in more recent times by the different Reid Vapor Pressure fuels (even more volatile that the old "winter blends" we had back then!), which are not necessarily tied to octane ratings or ethanol content per se (although ethanol CAN be in that mix, too).
The other side of these more volatile/evaporative gasolines we now have is that once the engine is running, that comes out of the venturi cluster should be more vaporized by the time it gets into the cylinders. Which should result in better combustion, as a general rule.
Of course, fuel-related drieveaiblity issues are more likely in the early spring of the year, by observation. Even on EFI vehicles. Although the "fall blends" might not get the visibility as the "spring/transition blends" do, they might not be that different? It's getting to that time of the year when refineries go offline for their seasonal changeover for the summer driving fuels/season.
Just some thoughts,
CBODY67
