1971 280s shutdown upon warmup

hi. i have a 1971 280s 6cyl. gas. the car sat for about 3yrs. i've got it running great while its cold; but it seems like every time it gets to normal operating temp it quits . there is no sputter or miss beforehand it just quits like i turned the key off. after it quits it will not start untill it has cooled down considerably. does anyone have any idea what could be causing this problem? thanks in advance.
Louis Bennett

[Mark DiSilvestro]

It's always hard to diagnose without seeing the car, but the first thing that comes to my mind is failure of the transistorized ignition unit. Immediately after the engine quits, check to see if there's no spark at the high tension coil wire.

Happy Motoring, Mark