Thinking I'm going to need a new alternator soon and will be headed to a Pick&Pull early next week; was thinking of a bigger more modern alternator for my 89 Grad
azALFAowl:
As I always ask in these situations, what is wrong with your existing alternator? Do you think it is wearing out? Battery not charging? Headlights dim? Have you added a lot of power-hungry accessories?
See what Papajam and I wrote in posts #6 and 7 in that 2012 thread which you cited. Unless you need more current, a larger capacity alternator won't buy you anything.
While spica-era Alfas did have pretty wimpy alternators, I
think that by 1989 Alfa had upgraded the capacity, as well as transitioned to internal, solid-state regulation (can anyone confirm this?). So while I can certainly understand converting a '69 to a bigger/later alternator, I'm puzzled why someone with an '89 would need to.
If your alternator seems to be wearing out, and if it is the type with the one-piece brush/regulator assembly, just replacing that part may solve your problem.
But hey, if you want a "science fair project", adapting a 120 amp Suburu alternator to your '89 Alfa could be an interesting challenge. Just don't expect any benefits beyond bragging rights.