Alternator with more amps than FD
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Does anyone know where or how I can get an alt that will put out something like 200 amps? I've already got an FD alt from Silverrotor, but would like to see higher amps. How about rebuilding the FD to put out more. Anyone know about that?
Thanks,
Rob
Thanks,
Rob
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Originally Posted by robfeltner
Does anyone know where or how I can get an alt that will put out something like 200 amps? I've already got an FD alt from Silverrotor, but would like to see higher amps. How about rebuilding the FD to put out more. Anyone know about that?
Thanks,
Rob
Thanks,
Rob
Speaking of mounting, do you have an air pump or the power steering/air rack? If not, you could add another alternator to run your stereo stuff. I'm pretty sure someone makes mounts for both the power steering and air pump locations.
I've been tempted to try and mount my alt. at the vacant air pump location to clean things up a bit.
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No, you can't run any alternator you want. It's not linear like spinning it faster creates more power. It's specifically designed to only run at a certain level of power based upon the number of windings, size of motor, etc. By that logic I could take an electric remote-controlled car and just spin it 10X as fast for 10X the output. BS.
As far as dual alternators, sure, what the heck you trying to electrocute? An elephant? Duals are for people getting 400A or greater.
There are plenty of options out there for bigger alternators. Mine for instance has an external regulator that provides 250A continuous and it looses efficiency around 280A+. It all depends upon how much power you want, what other accessories are running (lights, AC, heat, etc). If you have a big output stereo you should also be concerned with the wiring system of the whole car, not just providing more power. Keep in mind all the stock wiring has been rated for 80A only, not 250 or whatever you're going for. You will also need to isolate circuits from one another to prevent feedback, like to your ECU, fuel pump, lights, etc, as having that great an increase of power will require separate fuse/relay systems to keep power going only where you want it. Feedback is a very bad thing to your ECU by the way.
Any particular reason why you think you need more power than 90A?
As far as dual alternators, sure, what the heck you trying to electrocute? An elephant? Duals are for people getting 400A or greater.
There are plenty of options out there for bigger alternators. Mine for instance has an external regulator that provides 250A continuous and it looses efficiency around 280A+. It all depends upon how much power you want, what other accessories are running (lights, AC, heat, etc). If you have a big output stereo you should also be concerned with the wiring system of the whole car, not just providing more power. Keep in mind all the stock wiring has been rated for 80A only, not 250 or whatever you're going for. You will also need to isolate circuits from one another to prevent feedback, like to your ECU, fuel pump, lights, etc, as having that great an increase of power will require separate fuse/relay systems to keep power going only where you want it. Feedback is a very bad thing to your ECU by the way.
Any particular reason why you think you need more power than 90A?
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I do have an amp that could draw as much as 40A if I've got the thing cranked. Main problem is I added a monster E-Fan...which is the best thing I've done to this car. Sitting in central FL traffic in August is no longer any consideration. Anyway with the FD alt everything seemed to be fine. but last night on my way home, the info cluster lights came on for a second and my volt guage was dead on 12 volts. For the Alt, I made heavy duty charging wires to replace the stock crap, and I replced the grounds on the car and the positive wires from the battery. Like I said, everything seemed to be okay for about the last six months. I don't know what happened last night. I'm going out this morning to start the car then disconnect the neg side of the battery to see what happens.
Thanks for writing.
Rob
Thanks for writing.
Rob
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quick update: My battery is completely dead. Charging it now. Jumped car and it started and ran without the battery. E-fan came on and the car died immediately. I'm on my way to autozone to bench test the alt. It may be possible that I drove home last night pretty much on the battery...that would explain why its dead now.
Rob
Rob
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What E-fan are you running? I use the flex-a-lite Black Magic fan with my stock TII alt and have no problems. My FD alt from silverrotor arrived the other day but I'm not home to install it. ![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
Zach
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Zach
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You don't need a bigger alt. I was running 6 10 inch subs in my 86 for 2 years with the fd alt. Never had a problem. Just get your's rebuilt. Some places will add extra windings for you if you ask, however when I spoke to the guy I use he said it would decrease the life of the alt. Put a new one on and check for wiring problems. Probably just a dead alt.
Brent
Brent
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Yeah, I thought to just have it rebuilt here locally. My grounds are fine, I just replaced all that stuff a few months ago, and new battery cables, and new alt charging wires. I'm not 100% cofident that there's not a short somewhere, but my logic tells me that a short couldn't last that long as it would burn itself out and anything that has a fuse would simply blow the fuse...so I don't think that is it.
The e-fan is from a late model full size ford. Lincoln I think. It does suck amps. However, it does a GREAT job cooling this car off and that is a must for me. I drive every day in Orlando. My A/C has never been cooler, etc. The fan has two settings, one hi one low. I've got it on the high right now, could change it to the low and see what happens.
Rob
The e-fan is from a late model full size ford. Lincoln I think. It does suck amps. However, it does a GREAT job cooling this car off and that is a must for me. I drive every day in Orlando. My A/C has never been cooler, etc. The fan has two settings, one hi one low. I've got it on the high right now, could change it to the low and see what happens.
Rob
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Originally Posted by brent clement
You don't need a bigger alt. I was running 6 10 inch subs in my 86 for 2 years with the fd alt. Never had a problem. Just get your's rebuilt. Some places will add extra windings for you if you ask, however when I spoke to the guy I use he said it would decrease the life of the alt. Put a new one on and check for wiring problems. Probably just a dead alt.
Brent
Brent
If you're above 80% of your rated output of your alternator, you have too small a unit. Just because there were no problems doesn't mean you didn't shorten the life of it or excessively loaded it.
The motto here is simple; over-engineer and under-utilize. This way you will always have enough spare capacity to handle whatever happens. Taking the route of guessing..."nothing broke so it MUST be ok, right?", is foolish and dangerous. If you're serious, treat your car like an airplane. Would you do something to the fuel or electrical system that might make you fall out of the air or are you going to engineer it properly to ensure it will work?
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I agree with you, and originally thought I was fine with the FD alt. I'd really like to find an alt worth 150A and I think that would give me enough capacity to power everything and keep the electrical system charged without any problem. Has anyone rebult a stock unit to put out more, from a alt shop etc?
Rob
Rob
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I took my FD alt to Wrangler Northwest (they used to be contracted by Pheonix Gold for production of their alts.) and they told me nothing could be done to raise the amperage of our mitsubishi-made alternators. I think the only way to do it would be to retro-fit an alt from another car
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