Boiling fuel in your intake can be caused by a number of things like inadequate cooling system, lean mixture, poorly vented engine bay or more than likely timing and tune.
Not enough advance will cause the fire to be still burning in the cylinder heads and exhaust instead of the cylinder.Headers can cause excessive engine bay heat.
But a lot of guys do use an air gap style intake.
I completely agree. It’s 8-10 factors. A crossover is enemy #2. Ethanol is enemy #1. But, as you stated. There are several things we can due to help address the issue. I prefer to address them. Hence, the Air Gap.
