I have a problem with my Holley 600 (4160)

Back in the day, another thing we used to do is a flat aluminum plate under the carb between 2 thick gaskets with the same throttle bore pattern as the carb gaskets... It was intended to keep the heat away from the carb... Someone must still sell them and they don't raise the carb up that much... I think I used two plates back in the 70's on a 440... Part of the problem maybe the gas and how much alcohol is in the gas, you might try a different brand and see if it makes a difference... And of course that's what the intent of the Carter thermoquad was, as it dropped the temp of the fuel some 20 degrees... Good luck.... P.S. make sure your engine has not lost any of it's cooling ability, especially if you have a clutch fan, if they start to fail it can add more heat to the engine....