I have an older set of cast iron superstock SBC cylinders heads and matching intake, both of which have some epoxy or Belzona in the ports/plenum area. Does anyone have any experience using alcohol with heads or intakes like this? I thought I remembered hearing alcohol would deteriorate the epoxy/Belzona, but I can't help but believe that some of gasoline fuels have some pretty corrosive properties to them as well.

Belzona is fine with alcohol. It won't bother it.

I'd do some sort of test before I bolted everything together.

I can't speak to the exact materials used, but my brother bought an engine from a gas guy that had screens epoxied in the lifter valley area. It wasn't one or two weekends on a fresh build with alcohol before those screens fell down and got chewed up, with the pieces spread all through the engine.

Alcohol will deteriorate epoxy. But, that doesnt stop me from running ports with epoxy in them. I do however run a screw thru the floor of the port in to the epoxy to help hold it in place. I can usually get about two years out of them before I have to redo the epoxy. What happens is the epoxy starts to get under the edges until it finally gets under far enough to make it come loose. Then bad things happen when the chunk of epoxy tries to go thru the motor.

I've never tried the Belzona before so I cant speak of it.

I have an engine that was a gas motor and had Epoxy in the intake. It came loose after 2 years on alky. Went down and hung a valve open. Piston hit valve and you know rest of story.

coat the epoxy POR15 it will stop the alky from getting to the epoxy