I have boiling issues with my car as well. Unfortunately, no stations in my city carry non-ethanol fuel. There is a VP Racing Fuels distributor about 15 miles away but a real pain to get to. I am thinking about buying a drum of VP but not sure I want a half-empty drum of gas sitting around, if you know what I mean.
I've gotten in the habit of turning off my fuel pump about a mile before my destination to drain the level down in the float bowls. Since doing that I haven't had any problems with fuel boiling out of the carbs (I have Webers) and onto the intake manifold.