Improve your classic by upgrading your alternator


Part of the joy of owning a vintage car is its simplicity and purity of design. Compared to modern cars, the engine compartment in a vintage car is laid out in the way that The Great Automotive Creator intended, with all parts clearly visible and accessible.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2018/09/10/improve-your-classic-by-upgrading-your-alternator


Can’t argue with the author’s logic of replacing the generator/regulator with an alternator. But somehow it just never appealed to me when looking under the hood of an old car with that modification. Over the last 35 years or so of driving my (converted to 12v) '52 Chevrolet maybe 1000 miles a season, I’ve only had to replace the regulator once…and that was just a week ago. And I may just fiddle with the points on the old one to see if it’s worth putting on the shelf and possibly reusing someday. The generator has performed flawlessly all these years. I’ve got a set of replacement brushes for it, but the ones in it seem to be wearing fine. Yeah, the lights do dim a little at idle at night, but it’s rare I’m out after dark with the car anyway. I am thinking of going with a Pertronix ignition, but that’s essentially invisible. Besides, those internal regulators fail as well. Arguably not as often, but when they do the first sign is a cooked battery. Just my .02.


Chrysler started putting alternators on its cars in 1960, They had a battery+ terminal (big wire to battery) and one small wire from the regulator to the alternator field connection (2 wires total). The early mechanical regulator can easily be replaced with a new look-alike electronic unit for about $20. The regulator has one wire in (12V +) and one wire out (to alternator field circuit). A fairly simple and bulletproof system.
The first Chrysler alternators put out about 35 amps, later 1960s units went up to about 60 amps. The wiring harness was designed for about that much load.
Don’t go for the big 100 amp plus replacement units because you like the chrome, it is too much amperage. Your vintage wiring harness will thank you. … Gary V.


I second that, partly for the same reason, partly because on our '68 Beetle it means more parts than just the alternator and it’s better done with the engine out rather than in. Engine in-out isn’t tough either, but the whole swap would take a full day that I could be driving it instead. Or fixing something that’s actually broken! And much like your experience, our generator has given us no grief over the 20 odd years we’ve had the car. Maybe if I were rebuilding the engine I’d consider it, but the 40W cassette deck is the only non-standard accessory and it doesn’t take much juice. Besides, the generator is sleeker and prettier looking in the teensy engine bay!


There is a solution - The Powermaster PowerGen - it looks like a generator, but it’s an alternator -will put out 60 amps at idle, 90 max.
go to the link below, and scroll down a little past half way to see a photo
of their #85201

They are available from Summit Racing & Speedway Motors. I would imagine also from Jeg’s and other sources.


Replacing your alternator with a higher output version is good advice unless you own a vintage correct Mopar. The reason is that all the current travels from the engine compartment through a bulk head connector to the dash, where it goes through a real ammeter. Then it travels back out through the same bulkhead connector located on the firewall. These connectors were never designed to take the high current of modern alternators. The connector can fail, leaving your car DOA while driving. Worse, if the connector is oxidized, the extra resistance results in high heat - in the best case burning the bulkhead connector assembly, in the worst case an engine compartment fire. More than one Mopar has gone up in flames due to this. If you upgrade, you must bypass the bulkhead connector. Ask me how I know.


I did not know that ! My last Mopar was a '63 Plymouth ex-police cruiser
which had been equipped with a Leece-Neville alternator. When I bought the car from the local Yellow Cab company for $200 to put the drivetrain from my wrecked ex- Fed '62 Plymouth into, they kept the Leece-Neville unit and the dome light. I sold the freshly overhauled 318 to a friend for his "63 Dodge, and installed the factory blueprinted 361 out of the "62 into the Yellow Cab. It was great fun surprising the crap out of people at stoplights - great sleeper !


Forgot about those. I’ve seen them listed at Summit Racing. It sounds interesting, just wonder how it would play with the stock gauge.
That sure is a cool engine regardless…right down to incorporating the dummy fuel pump and bowl filter. :ok_hand:


@ctjagman - I purchased a rear-engine van a few years ago with an ammeter installed. That was terrifying. In modern times, I don’t see any reason for anyone to have an ammeter. I installed a voltmeter and was able to sleep at night after.

All that wire with all that current that really didn’t tell me anything a voltmeter couldn’t.