I've got a 65 dodge dart, 3.7L 225 and it continues to overheat. It has a brand new radiator, thermostat, water pump, and temperature sensor. I have flushed the engine and used chemicals to help remove any rust. Im not sure how big a difference it would make but the fan does not have a shroud. It will heat up faster during idle or when I'm in speeds excess of 40mph. I have searched other forums but have yet to find any useful info that I haven't tried.