How much extra amperage can you expect to achieve by getting the alternator rewound?

[cad_3326 10+ year member]

I've been searching for this and can't find it anywhere. If there's no straightforward answer then just give some examples. How much does it cost? Is it worth it, or can it be? Basically, if I need only 20amps or so extra, would this be a smart way to get them?

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[audioholic 5,000+ posts]

I've been searching for this and can't find it anywhere. If there's no straightforward answer then just give some examples. How much does it cost? Is it worth it, or can it be? Basically, if I need only 20amps or so extra, would this be a smart way to get them?

I find it hard to believe you NEED 20 more amps. If your alt is that close to being adequate, generally you can work with it.
As for respins, there is not straight answer. With a respun alt, they basically take the thing apart, remove the copper windings, and replace them. In the process they wind as much copper into it as possible, presumeably mmore than it had in its stock form. More windings/copper = more output potential.

The limiting factor on a respun is the actual alternator casing. The casing is only so large it will only accomodate so much copper in it before it is full. This is the alt's physical limit.

The reason there is no straight forward answer? Not all altnator cases are the same size, nor do all alts get spun to the same capacity from the factory. One alt may able to rewound from an 90amp unti to a 140amp unit (thats how it went for my old s-10 blazer) while the next setup may already have the maximum allowable copper windings in it from the factory so that a respin wouldn't help by one single amp.

If you are curious about your veicle/alt specifically, call your local alt shop that would be doing the job, they'll likely know off the top of their heads. lastly, if you DO get a respun, most shops seem to work on the basis on exchange. You give them your stock unit, they install someone elses old stocker that's been respun. If your alt just sucks at life (too small), it is also possible to mount different style alts with custom brackets. I would use that as a last resort however.

 

[kingkong101 10+ year member]

What about your belts/ pullies you can overdrive the alternator you know..

 

[audioholic 5,000+ posts]

What about your belts/ pullies you can overdrive the alternator you know..

Overdriving your alt does not change its max output, only helps (somewhat) when your car is sitting at idle.

 

[kingkong101 10+ year member]

Well, some alternators from the factory are not acheiving their max output BECAUSE of the pullies, like if you got a 150 amp alternator people dont realize that your only half way their, overdriving it helps even more.

 

[audioholic 5,000+ posts]

Well, some alternators from the factory are not acheiving their max output BECAUSE of the pullies, like if you got a 150 amp alternator people dont realize that your only half way their, overdriving it helps even more.

Uhm, no. Again, an underdrive pulley will mainly only help at low rpm (idling at a stop light or whatever). Once the engine spools up its RPM's, the output on the alt increases either way.
Running an underdrive will also lessen the life of your alt, keep that in mind.

 

[dragnix 5,000+ posts]

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[cad_3326 10+ year member]

Well, I can see why you would say I don't NEED 20 more amps, and I haven't made the install yet, so I can't say exactly, but I'm thinking that I'll have a little dimming, etc. I'm looking at running 1000rms total on two amps. I've got two cars and I can't decide which I cant to do my install in- I've got a Taurus, which has a 130A alternator, and with the big 3 I'm thinking that it'll run the 1000rms pretty well... I might want to get a new battery, but don't even know if I'll need that. Then, I've got a stratus with a 90 amp alternator, which is (I think) going to be underpowered, so I was thinkng that I could get the alternator rewound, and if I could get up to 115A or so afterwards, then I could exchange my battery for a yellowtop (maybe wouldn't need to) do the big three and I'll be OK. Tell me what you think about the two scenarios... I know that its kinda hard to tell what kind of power the car itself is draining, but just from what you can say: Are my expectations of the power requirements and solutions legitimate?

 

[audioholic 5,000+ posts]

Well the closest scenario Ive had was running about 900 watts off of a 140amp alt (respun), big 3, no caps... had zero dimming even at full tilt.

 

[bass_lover1 10+ year member]

I'm running the 3 amps in my sig on a factory 90amp alt, and zero dimming.

Only upgrade is the factory ground at the battery was upgraded to 0awg, because I had an extra 8 inches of it.

 

[jdawg 5,000+ posts]

What engine is in your Stratus? Alot of chrysler engines use the Denso alt small case. My 90 Daytona has one, i researched it a while back and i beleive the 2.0 and 2.4 in the Strarus does too. They just change where the hook ups are for the feild wires and power wire. My car has a 120amp in it factory, but if need I have a 160amp from a Durango 5.9 with fire truck package sitting in the basement, got used for $50. Possibly may need a washer or 2 to shim it but the mounting points are the same.

 

[kingkong101 10+ year member]

i did mean idle i apologize

 

[kingkong101 10+ year member]

underdrive takes AWAY from the alt, overdrive is the opposite. And just to tell you as the rpms raise underdrives are still taking away from the alternator just not as bad as idle.

 

[Rich B 5,000+ posts]

What engine is in your Stratus? Alot of chrysler engines use the Denso alt small case. My 90 Daytona has one, i researched it a while back and i beleive the 2.0 and 2.4 in the Strarus does too. They just change where the hook ups are for the feild wires and power wire. My car has a 120amp in it factory, but if need I have a 160amp from a Durango 5.9 with fire truck package sitting in the basement, got used for $50. Possibly may need a washer or 2 to shim it but the mounting points are the same.

I believe I have the same alternator as yours in my 01 Eclipse with the 2.4l engine.

Do you think the Durango alt would fit?

 

[jdawg 5,000+ posts]

I believe I have the same alternator as yours in my 01 Eclipse with the 2.4l engine.
Do you think the Durango alt would fit?

that alt is probably different, the 2.4 in the clipse is a mitsubishi engine, I was talking about the 2.0/2.4 chrysler engine which would be in the stratus 4 dr, the 2 dr was the same as the eclipse, should have cleared that up