[Formulajones]

It's the pertronix lol.

I don't trust those things. Had a set in my bird back when they were only a pertronix 1. It did the same thing, would get warm and shut down. Only did that on the highway with extended time at rpm. Back roads were fine. I could park on the highway about 20 minutes and it would refire like nothing wrong. Drive another 5 miles and shut down again. Sent it back in to pertronix for testing and they did find something wrong with it. Sent another new one free. Installed that and same thing. Drive around back roads for 2 weeks and fine. Soon as I hit the highway it shut down withing 5 miles.
I reinstalled the points and it's been perfect for the last 20-something years. Ran the same set of points for 15 years without a single issue. I run the accel points in everything here that still has points (4 cars) and never a problem.

I came to the conclusion that the pertronix did not like the Pontiac with the distributor buried in the back basically under the intake with little to no air flow. Gets hot and shuts down, because I had better luck on Chevrolets and fords with that pertronix where distributors weren't so buried and had better exposure but these days I avoid the points replacement junk and just prefer points, very simple and never lets me down.