base timing keeps advancing by itself...

OK it followed using another distributor, I am assuming a points one sice all the electronics are in a petronix. Really a weird one Cooling down sure seems to be a electrical issue. What exactly is in your ignition ststem from the ignition power all the way?

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I didn't take it that way. I took it to mean he rebuilt the distributor he had, not that he installed a rebuilt unit. Communication works so much better when complete and correct sentences are used.