Odd cooling issue. Would appreciate input

[j-c-c-62]

If you’re not worried about stock appearance, you could get some electric cooling fans that will stay on when the car is shut off until the car cools down.

I wonder if this is a solution that may worsen the OP's situation. Being if the engine and the thermostat are still hot after shut off, and the radiator water has been cooled by the delayed electric fans to ambient temps, the first water that the hot engine will see after a quick shut off will be a big slug of relatively cold water until the thermostat can close, and that cannot be ideal.

 

[OMTWF-72SE]

My 72, 10 mins after shutdown is hot as ****. Not rad cap blow hot, but gurgle gurgle hot. Get a laser thermometer and check how hot that block gets once the water pump isn't moving.

 

[Virg464]

Just shooting in the dark here: is there another crank that would fit a 383 block but be from an earlier smaller displacement engine, 273/361, that might have smaller crank flange holes?

 

[autoxcuda]

It doesn’t seem far of now.

Does it have a fan shroud yet?

Put one on, it will help at slow speeds and some all around. Make sure it seal to your aftermarket radio well. Add insulation foam if not.