Gas boiling

Took the Barracuda out for it's maiden voyage today, about 70 miles. Some small issues I have to check. After about 35 miles I stopped at my son's house to check things out and to let him have a look see. Right off the bat we noticed that the gas was boiling in the carb.. The car was not running hot. I have a Holley street avenger 80770 on a M1 MP intake. The engine is a 360 magnum/390 horse MP crate engine. I don't think I can get much of a spacer on it, maybe a 1/4 to 1/2 inch. What would make the carb so hot to boil? Temperature was about 84 degrees. Engine temperature 185-190. Besides a spacer what else can I try if that doesn't fix it?