140 amp alternator upgrade install HELP!

hot air 84GN

Member
Joined
May 7, 2009
Hopefully some of you guys that have done this can offer some insight. After searching and reading post/threads for a week so, I am still not fully convinced on what to do. I am picking up the 25503134 bracket tommorow, an alternator for a 97 Camaro (LT1), and a wiring adapter 85854 (doorman).
I guess I might have to re-clock the housing. Exactly why, I am not sure of. I'm guessing for the wiring connections? And I have read that I will have to remove my v-pulley off of my original alternator and put it on the new alternator since it comes with a serpentine pulley.

The biggest question I have is about the wiring connnector. My wiring adapter plugs into the alternator (obviously) then has 3 wires. Red, brown, and black. Red for 12 V power. Is that correct? Then the brown wire from the adapter....does that connect to the wire that eventually connects into the coil/module area? And from what I have read, the black wire does not get used? I think.

On my hot air alternator, I had a post that read "batt" and had all of my wires connected to it with ring connectors. One from the positive battery post, one from my hot wire (fuel pump kit), and one that I traced back to the coil/module. On the alternator side of the "coil wire" it is factory brown and it reads: fusible link. Is this right? On my hot air alternator, there are two spade terminals on the top of the alternator. One spade terminal is connnected to the "batt" post as well as the other 3 wires.

Also does the new 140 amp (LT1) alternator have a post for ring terminals? Or does everything connect through the wiring connecter?

If anyone could help me out, it would be much appreciated.
Thank you, so much!
 
  • Oh I see, I think. Thats the link that I've been refering back to, and trying to decipher. Seems like nobody ever resolved which wire(s) to use. Or maybe I'm just a little slow and hard headed :rolleyes: I am finally starting to get that Ahh-Ha moment!
    Everyone seemed to agree to hook up the brown wire to the engine harness wiring....Black and red wires do not get used. Correct? I believe that voltage should be carried through the engine harness, and the alternator is grounded already. Its starting to make more sense to only hook up one wire.

    So, from what you are describing I would only hook up one wire to the pigtail connection on the alternator ("one wire alternator") Right? I think it might be slowly burning into my brain now.

    Thanks again
 
Your Dorman 85854 wiring adapter looks like this. The only wire you should need would be the brown wire that goes to the brown wire that excites your existing alternator.
85854-007.JPG

S - Sensor - The Red wire on this adapter goes to the voltage sense input in your voltage regulator. Many folks feel it is needed. If your wire from the main output terminal is large enough (minimum 8 gage) you should not need.
F - Field - The Black wire on this adapter goes directly to the field in your alterntor. This is used by some model cars to create a higher output, but should not be needed in your case.
L - Light - The Brown wire on this adapter is the exciter circuit. This passes through the alternator light in your dash. The light glows before your engine starts showing current is going to the regulator. Once the alternator is working it does not pull power throught the light and it goes out. This can also be hooked up to any power on with key on circuit as long as there is a 35 ohm resistor in the circuit. Too high a voltage on this terminal and your alternator puts out too much voltage.

Hope this helps
 
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