2nd gen or later alternator upgrade?

[dkopp]

hello,

my alternator (1993 SS) is starting to howl pretty loud, so i'm getting ready to replace it. has anyone compared the 90- or 110-amp alternators from the 2.5l and 3.0l engines to see if they are a viable replacement option? i recently did this on my 1986 300zx turbo. it's easy enough to determine if the clocking is the same. more so, i wondered if the bolt diameters where the same. i know the pully for the 110-amp is 6 grove rather than five. i found with alternators for the Z that the 90 amps stayed the same while the 110-amps had a different bolt diameter and needed to be drilled out. the casing changed slightly, too, which required grinding or modification of the adjustment strap.

anyone tried this?

thanks

btw - search didn't reveal anything...

[Deride]

Wiring plugs are different on the newer subies, as for the bolts they should bolt right in.

[ciper]

They are all compatible up to at least 2007 assuming you switch the plugs to the right type.

[Legacy777]

Yeah they are compatible. You just need to swap plugs. I'm running a WRX HO alternator. Our alternators have a 3-wire setup, and the newer ones are 2-wire. The third wire is a turn-on signal.

I'm pretty sure there's a link around here from me for the place I got mine in north Texas. If not, I'll have to dig it up when I get home.

[dkopp]

now this is a pickle b/c i was planning on buying a Napa alternator b/c it comes with a lifetime warranty and some other perks (free roadside assistance, which i'll never use), but i have to have it installed by a shop to maintain the warranty. that'll pretty much be null and void when i swap the plugs. since i don't run any additional electrical load, i'll really need to think about this.

if i understand correctly, the plug swap would just require abandoning the 3rd wire turn-on signal? i'll need to find a 2 wire plug. i don't know the wrecker yards, yet, up here in maryland. fortunately, i have some time...

thanks for the help, everyone.

[dkopp]

alternator plug link for future reference:

http://bbs.legacycentral.org/viewtopic. ... &view=next