My 63 Valiant with a 225 slant six is suddenly dying after driving, usually an hour or so. Doesn't seem to matter in town or highway. It has an electronic ignition and runs very well but it will just shut off and I will coast to a stop. Re-start the car and be on my way again. Any suggestions?

Potentially a heat related issue, quite possibly a bad electronic ignition unit. I'd take it in and have it tested, but make sure they test it 3-4 times in a row so that it recreates the heat buildup it would see in real life.

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Used to own:
'82 Dodge D150
Erson 270 Cam, O/S valves, mild port work, ~9.5:1 compression

Currently fighting with an '85 VW Cabriolet

My other passion

Does it do this just once a day? Or does it drive another hour or so, and then die again? I would temporarily mount a voltage meter inside the car, maybe hooked up to the cigartte lighter, and see if the voltage drops when it dies. If it does, look at the charge system. If you can, hook up the meter to both sides of the ballast resister, to see if it is working. Since it is intemittant, you will need to place it so you can monitor it during driving. Does your gas cap have a vent? I dont; know when they started venting the tank. I know by 69 they were vented, but don;t know about 63. If the cap needs a vent, and you put a non-vented one on, it will run until the air runs out in the tank.
Sam

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