Brand new rebuilt 396 engine dies while sitting at idle once in a while like the key was turned off . Starts right up again and runs fine with a load through all 4 gears. Initially did it hot, but did it cold tonight. Idle set @ 800 RPM with a new Edelbrock Carb, HEI Ignition, headers, new fuel pump, new Mallory ignition wires, new voltage regulator, new starter, and new Optima battery.

Ideas ??

Thanks.
Nilater

Check the hot wire to hei for bare spots or breaks.Also check the battery cables.