Alternator Options And Opinions
 

Cross Post from Miata.net.

Hola! Although my car is mainly focused around the turbo and suspension, I do have a 1200W-RMS amp in there with 4 mildly upgraded speakers and a medium subwoofer. Add in the 50W HIDs and my desire to drive everywhere with the top down and the heater on max...

Well, you can probably guess that I find my battery too low to run from time to time. To further complicate things, I have a '00 (with a '03 alt) using a Mopar controler since I'm running MegaSquirt (see Alternator Control box from Mopar - AbeFM's Photos for details) which will seem to give me low 13V levels when everything is working.

The '03 alternator (Hitachi) has an "80A" stick on the side of it and I don't know if it's my controller, the alternator itself (I had this issue, but less often, with my original 2000 model alt), or I'm just plain using more power than 80A can supply. Its certainly borderline.

There are lots of big alternator enthusiasts who recommend these $500 and up alternators, which as best I can tell are optimized for putting out lots of amps at idle speeds for stereo contests and running big winches - but I DRIVE my car, so I'm really just looking for more steady state power at a low price.

I've seen mixed reviews about these: http://cgi.ebay.com/ws/eBayISAPI.dll...tchlink:top:en
Most say its fine but a lot seem to say they are bone stock. The seller (purportedly) says they are rewound with new diodes and an underdrive pulley.

I've heard you can get an alt off a millenia for like 90A, but I'm thinking I want to be in the triple digits. Does anyone know if there's something off a truck or whatever that I could make work?

Thanks!
-Abe.

Get your current one rewound? Or better yet, get a junk yard 94-97 one that doesnt need an external controller and get that rewound for moar powah?

Hmmmm, 100A, I wonder if I'd have to control it.

What does getting it rewound cost? Obviously rectifiers, etc, would need to be upgraded. The math says I need 100A to be even close, 80A makes sense it's falling short. There's a lot of TDI stuff in the 120-150 range, likely overkill but if it'd bolt up I'd be golden.

Spend time searching for higher amp alternators online or in catalogs at the local auto parts store. I did this for my Toyota truck and went from 60 to 100 amps with the same connection and a different length belt.

It was from a Camry or Sequoia or something.

The link below the alternator will tell you that its internally regulated
(Regulator Type: IR)
The problem with Subaru alternators is that the plug is on the wrong side and will be between alternator and block when you mount it.

there's plenty of mazda alts that are more or less identical (but the amperage) that should be PNP. If anything there might be the need for spacer/washers and/or a different lower bolt.

Old thread is old, but is the general conclusion here that the RX7 alternator posted above is the "go to" solution here?

correct.

Just remember you need the longer bottom bolt from the rx7 as well (or parts store)

Is this electrically plug and play, or did the RX7 alternators not send a signal back to the battery light on the cluster (not that it matters to Downmented's setup)


I thought the KL motor 626 90 Amp alternators where as close to PnP as it got. I'd be interested as my fuel pump dips when my FM big flow fans kicks on causing a momentary lean condition. Yes I need to tune voltage compensation but sometimes it kills my car entirely.

Was going to switch to a single 12" fan for the moment and try to work out ducting.

Wait, no the rx7 alternator is all heavy and has more capacity than you need. The Kia alternator is where its at.

Info?

Leafy isn't running A/C because race car.

A/C + Spal fan means needs moar amps for best results in my car. RX7.

Kia alternator is rated lower but seems to have higher real life output than the POS miata alternator. I was confused what alternator thread this was. I thought it was the one for men.

It's the one for cool men, apparently.

Sometimes, bigger is better.

Bigger is always better.

For 1.6 peeps the FC Turbo (RX-7 89-91ish) alternator is supposedly a direct bolt in. I'll find out this week when mine comes in.

And for 1.8?

@psyber_0ptix Confirmed that it bolts directly into the 1.8 as well without issue.