The alternator interchange thread.

**anarchyx34** · 3-9-07, 0:06

Over the years I've seen some requests for alternator upgrade options for our cars. I myself have always wanted something a little better than our puny 70 amps. I've discovered some things recently that are fascinating and useful.

While it's common knowledge at ATX GT's came with an 80 amp unit. What may not be known is that 2ndgen 4cyl alternators, which are easily available are also 80 amps and fit with very little modifcation. In fact the only mod needed is to swap your 1stgen pulley on, which requires drilling out the hole to fit the larger 2ndgen alt.'s shaft. That and the positive terminal requires a bigger eyelet. I'm running this setup currently and it works great.

80 amps not enough? Ok. How about this one?

What is it? This is a 100 amp alternator from a FD RX7. Does it bolt on?

You tell me. This is in fact a FD alternator bolted to my FE3. My friend bought it for his rx7, and I told him to bring it over so I can see if it works. It also requires swapping (and drilling) the pulley, and requires the longer FD bottom mounting bolt, but that was about it. It's physically larger than our unit, but fits fine. Belt alignment is spot on too.

Now I have some other ideas if 100 amps isn't enough for you. But I'm going to keep my mouth shut until i can verify it actually works. But if it does, it will be very sweet.

**allmazda** · 3-9-07, 0:17

Good info! The first thing that came to my mind is either unit much larger than the 1gen? If so how hard will it be to install it? We all know how little room we have to get the alt. out of the car in the first place. I would like to know if it is possible to install with engine in and the best way. I know most folks take it out the top by the canister filter.

Or perhaps not install the pulley until it is attached to the engine.

**anarchyx34** · 3-9-07, 0:20

Well the 2ndgen alternator uses the same case. So it's the same physical size. The FD alternator is definitely bigger, not by terribly much, but it might be just enough to make replacement in the car difficult. I should've taken side by side pics. I didn't think about it. I did have to move the adjustment bracket up roughly 1.5cm to accommodate the rx7 unit.

swankyeyeball · 3-9-07, 2:52

I have a 92 626 LX, 5sp with 113K. I recently installed an aftermarket system in my vehicle and found the factory alternator to be rather inadequate. After scouring the internet for an aftermarket solution, I found a place that sells bolt on alternators for my Mazda. I thought I would pass the information onto you all since some of you might be looking as well. I am in the process of ordering a 200amp alternator for my Mazda. They are kind of pricey, but I guess nothing comes cheap these days. I'll have to wait to install it until I return home from Iraq. The info is listed below:

Iraggi Alternator
121 Highland St.
LaVergne, TN 37066
615-287-7991

http://stores.ebay.com/Iraggi-Altern...nd-Electronics

They might not have the 200amp alternator listed on their site, but you can call or email them and they can answer any questions you may have.

**anarchyx34** · 3-9-07, 10:04

Excellent info. I wonder if they're as strong as advertised though.

**Zach** · 3-10-07, 16:28

anarchy...splain this drilling of the pulley?? Eyes confuzed. Spanks

**lucasmaximus17** · 3-10-07, 16:37

He probably means that he had to drill out the pulley that was on the original MX6 alternator in order for him to switch it onto the Rx7's alternator. Drilling the actual hole in the middle of the pulley out in order to it to fit over the bolt on the new alternator.

**Zach** · 3-10-07, 16:41

oh...so boring out the pully bolt hole? is this what you mean anarchy?

**anarchyx34** · 3-10-07, 21:45

Yes that's exactly what I mean. I brought my pulley to a machine shop and had them do it for $20 since I couldn't find a drill bit that big.

**Zach** · 3-10-07, 21:48

couldn't find one of these large enough?

**anarchyx34** · 3-10-07, 21:49

Didn't think of using one of those. I didn't really look all that hard. I just figured f--k it, let a machine shop handle it.

**Zach** · 3-10-07, 23:04

lol

still good to know

**lucasmaximus17** · 3-10-07, 23:12

Well damn, you said what it took me a paragraph to say in four words. I knew i was saying too much.

**tyler886** · 3-11-07, 19:57

I like it, except the Bosch part

The plug for the wiring harness the same on that alternator? I havent looked at mine in ages.....

-Tyler

**CraZyOne** · 3-11-07, 21:57

A 20B cosmo alternator should work too, I think the S4,5 & 6 guys upgrade to the 20B alternator when they need a few more amps. Its 120Amp but good luck finding one.