[WalterBright]

You make a great point. With the Dodge regulator, I seriously doubt it was just for the Dodge Challenger. It was probably used across the entire Chrysler line, for years. Enough cars were built to totally justify its design. I don't know when semiconductor voltage regulators appeared in a single package.

In 1972, the electro-mechanical regulator was also likely far cheaper than a solid state one. The car didn't have a single transistor in it outside of the (rather expensive) radio. (There was an upgrade available for the ignition to make it "electronic" - it had one transistor!) The alternator of course had diodes in it.

The rough 5V also enabled the instruments to be made cheaper.

[Aloha]

I thought by 72 they were using the electronic ignition module instead of points? I thought MY72 was the year it was introduced even?

[WalterBright]

The electronic ignition was an option at the time.