340 with edelbrock heads overheating

Early a body said
ok, so its getting late but i went out and sprayed some carb cleaner around the base of the carb. When i spray the rear of the carb where it meets the intake the car stumbles and stalls out. Looks like I have a vacuum leak. Could this be the cause of the overheating. Please say yes because i am tired of messing with this thing.

I doubt it.
In all likelihood, you have compensated for that air leak with the mixture-screws. All that happens with a big cam is that the idle-speed goes up. To get the speed down, usually you just retard the timing. and so, at idle, everything ends up copasetic.
Now that you have discovered it tho, you gotta fix it, lol.