GM Alternator Conversion Info

shotsy

New Member
Apr 8, 2005
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Oklahoma City
Hey guys it's probably been covered a dozen times but here goes again



Converting Your Ford GM Juice

gm12si_alternator.jpg


1. Take the old alternator and regulator out.
2. Get the 94 amp 12si alternator out of an 84 Camero
3. Reclock the back of the alternator so the 2 prong plug is facing the right side of the engine compartment.

IMPORTANT make sure that when you take the 4 bolts out of the back of the alternator that you lift up on the case only enough to get it to spin!! Lifting it up any more than about 1/4 of an inch will result in the springs coming out of the contacts (this is a bitch to get back together) Re install the 4 bolts.

4. Get a 5/16 drill bit and drill out the mounting bolt hole to accomodate your original starter mount bolt.

IMPORTANT cover all of the openings of the alternator with tape so that the shavings dont get inside the alternator.

5. Make a new shim for the mounting bolt (will need to be longer than the original shim)

6. Connect a jumper wire (16 gauge) from pin 2 of the modular plug to the main post "BATT".

7. Connect the main post to the + side of the battery.

I used the original charge wire that was hanging out of the harness. Now that Green wire with the red stripe that used to go to the voltage regulator is a perfect +12V hot key on source for the duraspark mod and the fan relays!!.

Super detailed wiring diagram

12sialternator.jpg


8. The #1 Terminal. (Marked with a "1" on the case) This terminal is used to connect to the dash warning light. For the warning light, a lamp is wired in series with a switched voltage source. During normal operation the lamp stays off. If the regulator is damaged, the #1 terminal provides ground, and the warning lamp will light. Usually.