1978 trans am carb ls2 alternator wiring question

[nevasuma]

I have been reading and searching for days now and I can't figure out how to wire up my new powermaster 230 ad alternator into my original wiring harness. i bought the holley pigtail for that alternator to connect to the brown wire (i-field). see attached picture. I know to connect one red wire from the battery to the lug on my new alt. My question is where do I connect the red wire (sensing) on my new alternator? Also, what do I do with the third red wire that is with the a/c line conn in the picture. Those two red wire (sensing and the bottom one) connects together in a 4 wire splice with 2 wires going to to 2 different spots on the bulkhead connector. if that is too confusing, let me know.

So what I have done so far is cut away that 4 way splice. So i have 2 wires coming from my harness going to FZ and CY on the bulkhead connector. I do not know where to connect them to my new alternator.

Thank in advance for any advise.
Jesse

[andrewb70]

Jesse,

Is the Powermaster alternator a later model LS alternator? If so, all you need to do iw wire the Holley pigtail to a switched v12+ source. Then the big output wire can go directly to the starter.

Andrew

[nevasuma]

yes it is a later model ls alt. it was advertised in their catalog as great for ls swaps. I ran two wires from the battery. one to the lug on the alt and the second to the starter. But what about the two red wires that go to FZ and CY on the bulkhead connector. looks like CY feeds fuse box and other stuff. I think it needs to connect to something.

[andrewb70]

Yes, you need to feed the bulkhead with a 10gauge lead, from the starter. That's how my GTO is wired.

Andrew

[nevasuma]

ok cool, thanks, I will try that!

[dccows]

Hey, I'm working on a 78 firebird right now and am in desperate need to know where you found that image. It would help me a lot and I would be very grateful. I hope to god this 10 year old thread gets checked soon.