GM Alternators

inertia said

I still service a buncha these vehicles over decades, all kinda owners/ drivers/ stereos/amps, - a couple are daily drivers.
You know how many regs I put on in the last, hmm decade, one.
Alternators, - none, - I have put brushes and bearings in 3 or 4.
My own vehicles/kids , none in decades, or since built .
I'm sitting on a wooden chair (embracing it, lol)
Cheers .
Who cares if the alt doesn't put out at red lights with appliances, wipers, heater on, - the car doesn't care .
Thats what the battery is for, ballast, and if you notice, 50+ years later, stock ones are still running around.

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Glad you have had better luck.

Additionally before I bought the car the alternator had melted the dash harness due to being stuck on full field

My friend has a 1971 Demon and the alternator that was with the car failed and the replacement also failed within a year. Now it's at a 12SI delco like mine for 5 years with no issues once again.

I do actually care about it working at red lights, it should at least maintain 12.8V -> same as a fully charged battery with the headlights and wipers on...and in my case the EFI fuel pump and the fans. Anything worse is not great. When you want to go someplace with traffic at night its needed. The battery should only get drawn from for miliseconds during transient and also during starting and that's it. Its not an original car any other way so I use things that work. Unlike many of the other things it was also really inexpensive.

Like I said this is a 78 amp alternator, but it can pretty easily put out 50A at idle which is vastly better for the load needed.