I am having trouble with a 318 V8 in my 1973 Duster. If I start the car and run it up to 180 to 200 degrees it runs great. I turn off the car and it will restart right afterwards; however if I wait for more than 15 minutes the car will refuse to start for upwards of 2-3 hours. This makes me think it has something to do with the engine heat. Does anyone have any ideas as to what the problem is?