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alternator install

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im installing my new 3g alt. this weekend, and am in need of some tech info.
im aware i am supposed to install a larger gauge charging wire.

the alt. i purchased came with instructions that simply state to cut the old plug off and connect both old wires to the new alternator connector thingy...
and conenct the small one to the stator plug.

should i definately install a new charging wire?
if so, do i need only one instead of two?
what gauge wire should i use??

is the current wire for the stator plug fine?
if not what gauge should i use?
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You will cut the 3 wire plug and simply solder the 2 of them specified to the new plug included with the kit. Then you will use the other one to go into the stator plug. The charging wire you will need to upgrade is the large wire that runs directly from your starter relay to the alternator. You need to run 4 gauge wire if you went with the 130, or 95 amp, and 2 gauge if you went with the 200 amp. Simply run that and you are done. If the alternator is bigger, which it probably is if its a 130 or 200 amp, then you must also grind the alt bracket slightly to fit the bigger alternator in it place.
okay i installed the alt. and im ******* confused.

how many wires should be coming off the alternator?!

i have 2 on the main post and then the stator plug.

these were the wires from the LARGE plug. then i have the smaller plug just plugged into the alt.

thats all i have.

car started great, idled smooth now. idle was high, i dropped it down to about 750 (from what i could tell, for some reason my tach is sticking now...)

the car feels good really, i guess ill find out in the morning if the battery isnt dead then im good.

but i think i might be missing the friggin ground cable???!
well, just an update

shes running great, better than ever.
idle is perfectly smooth, starts pretty quick (i might upgrade groud strap to make it a bit faster) throttle responds better, my gauges and radio work at the same time (lol) and best of all, that sucker is kicking out like 16 amps of charge!! totally unexpected. needless to say, 100 dollars well spent.

I'm doing the same upgrade to my 5.0 H.O. T-Bird ('88 model).I've got everything in the trunk,just need time to do it.Did you run a new wire to the sylenoid,or just solder the 2 wires together and leave the rest of the wiring alone that was already on the car?I was told two things,one,I need to run a new 4 gauge wire,the other,I didn't need to do that,just cut,and reconnect wires to new alternator.Thanks.
yea i didnt run a new wire. my car starts up just fine and im having no drain or ground problems. and im checking the wires periodically to make sure they arent burning or frying, but i dont think the will. everything is working great.

i actually didnt solder them at all. i ran the small wire to the stator plug, and took the two large wires and hooked them to the main terminal on the alternator seperately, each with their own grommet connector thing. works fine. you can solder if ya want, either way would work.

be prepared for some hardships tho
i had a tough time.

my 3g alt wouldnt accept the lower bolt without some filing to the alternator bolt hole.
for some reason it was a little to tight, but i got it to work.

its an easy upgrade, but no i dont think you need to run a new wire, just make sure your connections are good.
Thanks a lot.I'm going to do it tomorrow.I've got the time,I've got the alternator,i've got the bits and pieces.I don't have any excuses.You've given me the motivation to press forward.I'll post another thanks when I'm successful.
on the 3-g install you shouldnt hook the two black and orange wires up. just cut off the ends and tuck them away then run a new 4 gauge wire. if you dont do this i hope you have good insurance because your car will probably burn down. the factory wires wont hold that much amperage and they will burn up. take my advice and run the wire and be safe
I guess I'm in the club too, LOL.
I was going to do the whole thing today, but by the time I got the bracket cut to spec I had to go get the woman from work. Not to mention, I couldn't find the solder tube...:rolleyes:
Hopefully tommorow morning I'll be able to finish the install.
Amusingly enough, the stocker apparently knows its on the chop list, its suddenly started putting out 13+ v at idle.
I can't say for sure what its worth, but I went ahead and bought the PA wiring upgrade from the alt to solenoid. We'll see how it does, especially once I add the new ground strap.
Swap done,and it seems to be working great.I'll keep an eye out for bad things,but,so far so good.I let the car idle for about 15 minutes,nothing bad.I'll drive it tomorrow.More later.Stay tuned................
just to be safe, im gonna grab a new wire
4 gauge i here is popular lol.
this just runs right to the starter relay correct???

yo i just checked out my wiring because i was nervous.
those two black/orange wires become ONE wire inside the looming. the wire they turn into, the one that goes to the starter relay, is a 4 gauge wire. isnt that enough?? do you really need TWO four gauge wires?? ive seen 1000 watt stereo amps that wont come close to burning through a 4 gauge wire. or is this extra wire for something else? im really confused about this 4 gauge cable im supposed to be adding.

okay i did some research and found a page with a full explanation
that makes it very clear. check it out if you need clearing up on the wiring.
It's not 4AWG. The two 10AWG wires go into a single 8AWG wire/cable.

A 4AWG cable is the minimum required for 130A in a high temperature environment (such as in an engine compartment). If it were not in a high temp. environment, a 6AWG cable would be sufficient.
systronic said:
I just checked out my wiring because I was nervous.
Those two black/orange wires become ONE wire inside the looming. The wire they turn into, the one that goes to the starter relay, is a 4 gauge wire.
yea i got it now, thanks for all the help guys seriously. im just gonna run a new 4awg cable (a nice purdy red one) and leave the old ones connected too. overkill = safe :) ima get some pretty red wire looming too. might as well start my winter planned engine compartment restoration early

thanks again!
I kept the pigtails from the 130 amp alternators original wiring harness,and connected the large wire from the 130 amp pigtail directly to the one bigger wire from my car (where the two black and orange wires become one),and so far so good.I'll also upgrade to the 4 gauge wire just in case.
If you keep the factory wire(s) (10AWG and or 8AWG) in place, and the fused (you are using a fuse, aren't you?) 4AWG circuit breaks (for whatever reason, most common being one of more diodes in the rectifier shorting to ground), what are you going to do when enough amperage is sent though that stock wire to heat it up to the point of it melting the sheathing around it and the wires adjacent to it, and then catches on fire? Don't think it can't happen. It did to my STOCK alternator.

And don't plan on the fuse-link saving you. Mine didn't. Luckily I put the ensuing electrical fire out before it burnt the car to a crisp. Oh, and I had to replace the headlight harness because two feet of it beneath the battery tray was melted.

If the alternator shorts to ground, you want the circuit to break.
Didn't you read what I said?I'm putting the 4 gauge wiring on with a 200amp fuse..
I wasn't responding directly to you. My response was for anybody who thinks they don't need to upgrade the factory wiring OR that the factory wiring along with 4AWG cable is OK.
I agree with you 100% my friend.Better safe than sorry when your a long way from home on a lonely highway.The new wire is very cheap insurance.
okay so i took out the old wires, put in the new 4awg wire, loomed everything, made sure that every single wire in my car was covered.
basically i did a whole electric exam on my stang. i was hooking the battery back up (in a hurry, it was late) and accidently bridged the terminals. ouch, is all i have to say. my wrench actually melted. and my hand is fried. take your time fellas, its worth it...
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