Fox Body Alternator on a Classic?

jb1dsl

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May 24, 2004
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Marianna, Fl.
I have a fox body alternator and was wondering does anyone use these on the classics? Do they have more amps? How simple are they to install? Does anyone have instructions or diagrams? I have heard of using 3g's and one wire alts but was wondering if this was an upgrade? I know you will be able to get rid of the voltage reg if these are used.
 
I have a fox body alternator and was wondering does anyone use these on the classics? Do they have more amps? How simple are they to install? Does anyone have instructions or diagrams? I have heard of using 3g's and one wire alts but was wondering if this was an upgrade? I know you will be able to get rid of the voltage reg if these are used.

It's an upgrade with regard to amp output.

I wouldn't go with a 2g on my car because of the fire hazzard issues. I would step up the 3g just to be on the safe side.

http://fordfuelinjection.com/?p=75
 
I just had it on hand and was wondering, what is the fire hazard?

There is a TSB on it and that in and of itself tells me that it has to be a real problem. Ford doesn't issue a TSB unless they absolutely have to. It has to do with the wiring overheating.

Like I said I just wouldn't bother since the 3gs (from the taurus) are so plentiful.
 
How do i identify a 2g,3g, or 4g.
Can anyone ID this alternator, I believe it is from a fox body?
The numbers on it:
top side: X75A E7ZFFA F 07 9 B

Front (pulley side): 21

Back: 30
Take a look at the link below. All kinds off info which should help. Off the top of my head I would say that if it has a fan on the pulley then it's a 1g or 2g.


http://fordfuelinjection.com/?p=63
 
If you use a thicker gauge wire I think that would take care of the wire overheating. If you need a new alternator and you have one that will work, why not ? Altho, I recomend going to the 3g alternator as it is far superior and will put out more power with less load on the engine.
 
the 2G looks more stock than the 3G and a lerger gauge wire would cure the overheating issue. if it just want better performance and don't care about the looks a 3G would be the better option but if you want to retain a semi-stock look the 2g would be good.
 
I purchased a harness adapter from Mustangs Plus when I did an EFI conversion. It was a harness that adapted the original alternator wiring plug on your car to the fow 2g alternator . I think it was made by Ron Morris. It was a nice piece and made it real easy. Now that I have said that, I just converted to 3g using the wiring kit from fordfuelinjection.com because I need the extra juice for a new stereo. I should have went to 3g to start with.
 
My setup utilizes an alternator off of an E350 Ambulance package. Same goes for the voltage regulator. Mid-80's setup rated for 100 amps. I found this was the most stock appearing with higher amperage. I will be switching to a 3g shortly however.

To cure the overheating I ran an additional 8 gauge wire to the battery. I DID have a small electrical fire when I tried to run without it. Since then I have rewired a lot of the engine harness and don't plan on having any problems.
 
Here's some info that helped me when I converted to a 3G:

3GAlternator.webp
 

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Nice diagram. You can also hook the Yellow wire directly to the output terminal on the alternator itself, makes for a cleaner install and saves space on the starter motor relay.