Thread: 3 Wire Alternator swap help

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I am currently dropping a GM V8 into my 60 Bel Air that had an I-6. I am going with HEI and a 3 wire alternator. I have been researching the hell out of my wiring options and am trying to figure out the best way to rig up the alternator.

From my understanding (and please correct me if Im wrong) these are my plans:
-The positive lug on the alt will go to the postive lead on my battery.

-Spade connector 1 on the alt will go (in series) first thru my old generator light on the dash, then to switched positive lead on my fuseblock or ignition switch.

-Spade connector 2 on the alt will go to a positve connection on my fusebox or a positve junction.

I do not plan to jump #2 to the positive lug on the alternator. Though I know this can be done, I have read that the #2 is a sensor and needs to get an actual reading of the voltage in the harness. If I jump #2 to the lug, I get an incorrect reading causing the alternator to not energize enough to fully charge the battery.

Please tell me if I am on the money here or where I may be wrong. How did you do yours?

Thx guys!

This is how mine is wired, below and as far as I can see, the charge circuit works just fine. Right after start up the volt meter will go to 14-14.5V+/- then after a couple of minutes drop to the 13-13.5 range. I do have a diode in the line back to the ignition so the alternator wont try to motor after shut off. Here's a good web site to look at for alternator info:http://www.madelectrical.com/electri...hreewire.shtml

Thx Dave...I have been reading that site among other for a few days now. I see that you are jumping #2 back to the battery terminal lug. Most people do I guess. I have read that by doing this, you are essentially turning a three wire alt into a 1 wire alt. I am guessing that I may have bad info and will run it as you do. Ill do some more digging.
thx!

BTW Dave...great car! Where about upstate are you? We spend time at Sandy Pond in Pulaski every summer.

dont forget the diode or your engine wont turn off

Originally Posted by Gusaroo

BTW Dave...great car! Where about upstate are you? We spend time at Sandy Pond in Pulaski every summer.

If you look at the schematics, that 3 wire arrangement is about the way that GM did it tho they weren't quite as direct with the wiring. Theirs went to a light or meter instead of the anti-reverse current diode.

Thanks on the car - been my longest ever project.
I'm just off I-87 a bit South of Saratoga Springs which is quite a ways from Pulaski