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Dual alternator... let's kick this one around

Featured Replies

Has anyone tried mounting two alternators/two battery system?

 

One would run the main engine components and such and the other would be used to run all your other auxilliary components.

 

A stock alternator could be mounted in the AC bracket and the AC belt could be used to run it. It could then be wired to another battery.

 

I am not sure how a single battery would respond to double the amps.

 

Can anyone move versed in Auto electrical wiring/workings chime?

 

Thanks

 

BW

just my .02 but try getting a bigger single alt. much easier Qman should be able to tell you where he got his high amp one, if you need more power then that, then you are doing somthing wrong.

i decided on the same thing. two is alot of trouble, when you can get a 90 amp one to bolt on, from an xt6.

XT6 isn't quite bolt on. Gotta swap pullies and space it out properly so the V belt doesnt get thrown off.

 

There is also the GM 100 amp conversion.

 

Dual alts wouldnt be too hard if you take out the AC pump, fab up the brackets to bolt a standard one on and wire it in.

 

Some options to consider :)

I've got a dual battery set-upon my 82 Brat. in the process of putting in a 150 amp Streetwires alt. (rebuilt, from eBay). have had the 90 amp xt6alt up to this point with no problems, but have only used the winch once (right Morgan :) ? )

 

One note on the dual battery set-up... I'm thankful I had a good isolating solenoid. my xt6 alt wenthaywire and charged out at 17+ amps, and fused the main battery inside the cells....

XT6 isn't quite bolt on. Gotta swap pullies and space it out properly so the V belt doesnt get thrown off.

 

ok... its a bolt on that goes along with the er27.

but have only used the winch once (right Morgan :) ? )

 

Hey we had to make sure it worked right? Purely for testing purposes! :lol: I need MTs :(

 

===============

 

OK back on topic here.... So that one you bought on eBay is just a remaned Subie alt that puts out more juice? Or am I reading that wrong?

 

Thx

Hey we had to make sure it worked right? Purely for testing purposes! :lol: I need MTs :(

 

===============

 

OK back on topic here.... So that one you bought on eBay is just a remaned Subie alt that puts out more juice? Or am I reading that wrong?

 

Thx

 

No, it's a "Streetwires" brand (not made anymore) that was rebuilt. it's a 150 amp that has it's own ext VR that came with it....

  • Author

got it so basically pain of engineering the set up would would outweight benefits.

 

I already have the XT6 alternator. Just concernd about when it decides to buy the farm.

 

Ohh on another note, EJ Alternators output is 75 amps for the 2.2L impreza and the 2.5 Forester and 85 amps for the 2.5 DOHC motor. these were based on the 1999 models.

http://www2.autopartsauthority.com/parts/autopartsauthority/wizard.jsp?year=1996&make=SU&model=OUT-4WD-001&category=F&&part=Alternator

 

anyone thought of retro-fitting these to an EA motor?

Dual alternators would not be a good way to go imo. As above, the engineering costs would outweigh the benefits dual spinners would provide.

 

Usually when someone goes with dual alternators is only when one alternator will not provide enough power for the task at hand. And thats only when you've gone as big of a single alternator as you can go. There are plenty of options you can run with.. a pure bolt in 100A GM alternator, 90A XT6 alternator and whatnot. With my 100A GM swap, that opens up even more options, as theres numerous aftermarket alternators of much higher amperage that share the same outer dimensions and would therefore swap in for the 100A. If I had the funds, I'd go on ahead and get a 350A variant of the 100A swap that I found in a Jegs catalog last month. :) 350 amperes.. out of a single alternator... :slobber:

Wonder how much an alternator specialist shop would charge to recoil and pack a standard EA82 60a alternator housing to put out more wattage... might have to make some phone calls tomarrow when I'm bored at work :brow:

I've put multiple alternators in other cars, just not a Soob...yet. It really isn't all that difficult, you just have to remember that you are wiring in the second alternator parallel to the first. I went out this morning and took a couple measurements on my 83. It used to have AC and P/S, but now has neither. Looking at the brackets for this setup, I don't think it would be terribly difficult to add a second alt where the AC compressor is supposed to mount. Realistically, though, there's something to be said for just going with the single GM 1-wire 100 amp unit. The times I've done this were all in cars with either MASSIVE stereo systems (10000+ legitimate watts) or hydraulics (15-20 batteries with high-current relays to change their wiring from series for hydraulics to parallel for charging). I seriously doubt you've got anything in your car to warrant the presence of so much electrical power.

I checked at napa and if you get the higher output alt for a 79 olds cutlas V8 it is the same one that raven used for his swap. It was around $55 at my store.David

  • 2 weeks later...

You could always go with a Lecce Nevile alt. They have a couple of alts that do over 325 amps. I have been contemplating duel alts under the hood of my subaru to run a CB that does alot of watts, but If It does happen, it will be down the road. People have benn running duel alts for a while now, I'll dig up some sites ti visit about the installs.

  • 13 years later...

I have a 150a Alt in my '92 Legacy. Idk for sure what Alt it had in it when I purchased it. Alt started going out, I'm sure the audio setup I had at tge time hdlped her along. So I got a new one from O'Reillys. Never bothered to read what amp it was. Just slapped her in. Noticed tho, that with the freshy in, headlights were still dimming a bit when I was bumpin. Capacitors aren't my thing. I had 3farad Cap installed previously. Headlights dont dim, but the Alt still has to charge it. Anyway. So i started getting into Alt research. High Output Altenators, Dual alternators, Xtra Batt,  Batt Banks, Lithium etc etc. Which inevitably led me to call and ask what amperage I had bought from O'Reilly's. They said 70a. I looked around the ol' interweb and saw 220a Alts in Subaru's, 250a and even 270a. None that high for my car. The highest I found was 150a. I got it. Extra batt in the back floorboard between the seats. Optima YellowTop under the hood. All 1/0 Welding Wire running the system. Which is 2 EVL12's in a 4th order bp. 1 RP2K.1 amp. 4 6.5's. 2 Kicker  2 Pioneer. JVC HU. 

Im still pulling 200+ Amps in just the system alone. I'd guess the car is pulling +/- 50a? So im always drawing on my batteries. My Alt is always behind the system. Trying to keep up. So I'm interested in adding that brand new 70a to the mix. So....? Fab a bracket, get a longer belt, put it where you want. Replace AC stuff with the Alt?

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