drdave88

iTrader: (3)

I'm swapping in a 350 carbed into my V6 car. Do I need to keep the wiring from the harness that goes to the alternator or can I just run the 1 battery cable to the alternator? I will be running a serp belt set up so I'm not sure which alternator I can use, an old 1 wire or am I ok with the a V8 alternator from a 3rd gen?

Orr89RocZ

iTrader: (20)

There are various v8 thirdgen alternators. Some 2 wire some 3 wire. Not sure if any singles.

If you are using thirdgen serp setup, keep the wiring harness. The 2 wire runs one wire to the starter/battery connection point, and the second goes to the fan fuse. The 3 wire has both those and another wire to the L terminal, some setups use that for activating the alternator via ecm. I forget exactly where that wire goes, have to look up the diagrams. My 89 was 2 wire. The 86 firebird harness i have has 3 wire

drdave88

iTrader: (3)

I wont be running an ECM, so is that connector needed at that point? Would i need something else to control the voltage regulator (i assume that is what the connector is for)? I am cutting out everything that I dont need from the harness.

Orr89RocZ

iTrader: (20)

No the alternator harness is separate from ecm, unless its a 3 wire then one may go back to ecm. I am not sure but the 2 wire definately does not interact with ecm.

One big red wire goes to starter where battery power hooks to, and other goes to fan fuse block thru the driver side firewall connector.

I would use a alternator for the thirdgen serp belt setup and use atleast the big red wire part on the connector. If you use factory electronic fans then also keep the fan fuse wire or relocate a fuse and run back to power at battery to shorten the wiring

drdave88

iTrader: (3)

The big red one is separate from the harness I'm talking about. There is that one, then a (I believe) 3 pin connector that goes to the alternator. The harness ran to the V6 alternator that was on the pass side. I'm getting brackets from a 4.3L that has the alternator on the driver side.

If I understand right, you're saying the 3 pin connector controls the fan fuse? It has nothing to do with the voltage regulator? Also, I only have a single fan that will be controlled by a toggle switch. I will try to get ahold of a wiring diagram for it, that may clear up some of my questions.

Orr89RocZ

iTrader: (20)

Need to find a diagram for the v6 car. I thought they may be similar to v8, but i guess not.

vetteoz

iTrader: (13)

The Alt operates independently of the ECM .It needs the above noted input through a resistor or the idiot light on the L terminal to
excite the Alt so it begins charging

http://alternatorparts.com/cs130_sbpage3.htm

There is usually a input to the ECM but that is only so the ECM can monitor the system voltage and make adjustments accordingly
There is no feedback ECM to ALT or control of the ALT

On the CS-130 there is also a (3rd ) voltage sensing wire that the Alt used by the internal regulator to determine how much voltage is present
in your charging system.
In retro fits this is typically just looped to the main BATT terminal on the Alt

Orr89RocZ

iTrader: (20)

My 89 diagram only uses terminal S and F. L is not present. On my ls1 411 ecm, there is a ecm wire that goes to L but i am not wiring it in. I dont think its needed since i never ran it before

drdave88

iTrader: (3)

I got it now, ok cool. I bet that also controls the gauge on the dash. Thanks guys!