3G swap on 390, help please

[JoshT]

I've read the FAQ thread stickied at top, but still scratching my head a bit as to which alternator to get.

Okay, I'm rewriting this cause I rambled on way too much before.

Engine currently has a bottom pivot 1G alternator with 7" mount spacing. Things I've read online lead me to believe it should be 8.25" spacing, but I definitely have 7" on my alternator. It may be that the bracket has enough adjustment to be used with either spacing, I just know the current alternator is 7" spacing.

What I've read here and elsewhere 130a+ alternators will likely have issues with a single v-belt. It sounds like I probably need a 95a alternator for my 3g conversion to avoid any problems.

I've looked into the donor vehicle lists I can find here and elsewhere and everything seems to be returning a 130a alternator and of course nothing mentions mount bolt spacing.

Can anyone point me to exactly which vehicles used a 7" spaced, 95A, 3G alternator in a factory application?

[JoshT]

Looks like I might also be able to get my hands on a free ~100a 6G alternator from a 2002 Taurus. Seems that these will physically bolt into the same mounts as a 3G, but not sure about wiring differences or the pulley from the 1G fitting.

[JoshT]

Ok, so no replies. Site seems to have been a little slow recently, so not too surprised. Hope everyone is busy working on their trucks instead of inside hiding from Hurricane Michael like me.

Turns out that the 6G from the Taurus is probably not an option. Seems that some 6G alternators may work, but others like this Taurus are somehow controlled by the ECU and won't work without that input.

Ended up ordering the PA-Performance 1G to 3G conversion from American Muscle. They had the best price shipped for me. I know that the ammeter is less than ideal, but I like the idea of having it still working. Can't remember what the auxiliary gauges already installed in the truck are. I know one is a coolant temp gauge that doesn't work, if the other isn't a voltmeter, one will be installed soon.

Don't have any good pick-n-pull yards in my area, and the 3G alternators I could find used locally were in the $50+ range. At that price I decided to skip the headache and just buy a new/reman unit. Due to bills (both expected and unexpected) this month I need to penny pinch and really hunt for best price on an alterator. I think I lucked up on a steal, $25 for a reman 130a Mustang 3.8L alternator with limited lifetime warranty from one of the national chains. Once I've got the part in hand and sure of what I got I'll post more info for anyone else that might need a cheap 3G alternator, unfortunately it sounds like it will be at least some time next week before the alternator arrives.

I was wanting a 95a, but they seem to be phasing them out in favor of 130a units. All the applications I searched for that should have been 95a alternators, were returning 130a units as replacements. I think I'll be ok, but if I have issues I'll probably follow WhitsEnd's example on the idler.