[Tom Wells]

Bill,

Yep - been there - tried a return style regulator. This would help if the heat came in with the fuel from the tank. It didn't help. The problem seemed to be that the fuel already in the two float bowls got heated up after a while. Since that fuel didn't recirculate, the return didn't help.

The no-alcohol fuel is sold here in Florida all over the place but it was a rarity when I was having my carb misadventures. It is a couple of octane points lower (I think 89 vs 91 for our alcohol-laced premium I usually run); if that wouldn't cause your engine to knock it would seem to be worth a try. My engines are around 10:1 compression so I think it may have been OK.

The advantage to EFI is that it runs at 43.5psig all the way to the injector. The higher pressure prevents boiling. The pressure in a carb float bowl is 1 atmosphere, or 43.5 psi lower than the EFI.

Tom