Stall at idle at normal temperatureq

I have a problem that has been driving me crazy. Maybe one of you guys out there can help me. My '71 demon 318 ran perfect up until a couple of weeks ago. Now at normal running temperature, it won't idle at a light. It starts stumbling and then it eventually stalls. I can start it as long as I've got the throttle down at about 1700 rpm. Eventually it doesn't want to run until I let it set for about an hour or so. Last night I put a new eddie 600cfm on it and it still does it. Is it vapor lock? I did notice that the glass fuel filter I just put in didn't have any gas in it when it stalled today. I even insulated my fuel line going into the fuel pump. Fuel pump seems like it's getting pretty hot. carb seems hot too. In fact after it dies, if I throttle it at the carb, the gas smokes/vaporizes a bit when it touches the throat. The engine runs like a champ until after about 10 minutes of city driving. Any help would be amazing.