I have AC, 350 motor, what amp rating alt should I get for my car? It squeals some, may as well replace it while TC issue I am dealing with is fixed.
Belt issue? Squeal was the wrong word to use. It is a bearing going out type of noise coming from the Alt.
Those years used either a 37 amp or a 55 amp alternator . The 55 is used with AC . If you look at the case where the adjusting bolt is it should be marked .
The obvious answer is to stuff in a dirt-cheap, ultra-common 10- or 12-SI internally-regulated alternator. If your car came with a low-amp internally-regulated alternator, the 55--60 amp alternator is a fine upgrade needing no other mods. I prefer a QUALITY rebuilt Delco alternator to the horde of crappy Communist knock-offs sold as "New". If you had the 10DN external-regulated alternator, the newer SI alternator will produce more output at idle even if peak output is about the same. You need a harness pigtail and two short jumper wires. "Even a cave-man could do it". There are still-newer alternator designs that can give you in excess of 100 amps and still-better output at idle...but you're unlikely to need them.
I am keeping the car stock, no thumping tunes or anything that needs extra power. I just want a stock unit that the car has now.
The internally regulated alternators are superior to the externally regulated units, especially at idle. GM started using them in 74 or so? It is fairly easy to convert the wiring. They look virtually the same. http://www.buickperformanceclub.com/alternat.htm
Hell, yes. I thought the 10-SI was installed starting in '71 or '72, but American Autowire says they started in '69. I'm not sure I believe them. There was also a goofy short-production run of hybrids, external-regulated alternators inside internal-regulated alternator cases. I've never seen one in person. These folks also say the 10SI began in '69. What do I know? https://alternatorparts.com/how-to-identify-your-gm-alternator.html
You'd be NUTS to keep an externally-regulated alternator when the 10- or 12SI is so easy to convert to, inexpensive, more reliable and more output at idle. But then, your vehicle may already have a 10SI alternator. [Edit] You know that the OEM alternator amperage output is stamped-into the alternator case, right? You want to know what you have, all you have to do is clean up the case a little, and read it from the case itself. [/Edit]