1 wire alternator 170 AMP

[roll_the_dice]

OK, I am connecting my alternator and it is easier (less obtrusive) to wire it straight to the positive lead on the battery. I assume that is fine?

Also, I am using an AAW wiring kit and the alternator cable they sent is a 6 or 8 gauge wire with a fusible link. My alternator is 170 AMP that I got with my vintage air front runner system. I am worried the wire is not large enough to carry the current. Should I go with a 4 gauge for this alternator? And lastly your thoughts on a fusible link for the alternator? I know our trucks didn't have them originally, but this alternator is much larger than OEM also. Thanks

[The Rocknrod]

At 170 amps if it's up to 5 feet to the battery you'd use a 4 gauge. Longer run, bigger wire/cable.
https://www.motorcityreman.com/technical-info.html
Powermaster says the same thing.
https://www.powermastermotorsports.c...e_wires_a.html
I'm using a 3-wire 100 amp powermaster alt and installing an 8 gauge wire, there's no shame in me using a 6 if the run is longer.
We put much time and money in these units and being safe pays off.

[roll_the_dice]

Thanks...I just measured and with running the cable to the battery, I am right at 6 feet...maybe a tad under. I saw that same link before, but couldn't find it again. 1 gauge is so much thicker than 4. I would have thought 2 gauge would have been enough, but the price between the two are negligible. You are right...better to be safe.

[roll_the_dice]

I just saw the 2nd link you posted...interesting that their chart is slightly different. Up to 175 amp 4-10 feet 4 gauge over 10 feet 2 gauge.

[franken]

I'd be thinking about what max load current the truck will need to draw more than the max the alt can deliver. The alt delivers what's drawn, not what the alt is rated at (until the load is too great). What's more, electric motors for example are typically rated at max current/Watts rather than what the draw normally.
According to the internet, 2AWG is .25" in diameter, and 4AWG .2". What junction will be used and what feed wire size to what massive loads? There's no use in running a massive feed cable to a load that doesn't need it.
From a less devil's advocate point of view, I think later wiring feeds the alt to the big starter cable to avoid the long run along the driver's fender and core support. Then the feed to the connector by the MC could also come from the starter. Fusible links or other overcurrent protection might be a good idea in one or more spots.

[roll_the_dice]

That's a good point about the load. Nothing special going on with my amp draw other than A/C from Vintage air...I don't even have a radio yet, but will get one, but no big stereo system...just a radio with 2 speakers...no subwoofer or amps or anything.

I am going to run the wire from the alternator down to the frame rail across the radiator support and up to the battery...6 feet almost exactly.

[franken]

I know early in the thread Vintage Air was mentioned, but what draws current? The fan is minimal and the compressor runs off the engine, correct?
I'm just being a pain, but the point is, the rating of the alt means nothing and load means everything.

[roll_the_dice]

Originally Posted by franken

I know early in the thread Vintage Air was mentioned, but what draws current? The fan is minimal and the compressor runs off the engine, correct?
I'm just being a pain, but the point is, the rating of the alt means nothing and load means everything.

I just mentioned vintage air because that is who I got the alternator from when I bought their front runner system and A/C...in case anyone else had done the same.

But to your point, I don't think I have much load at all. The alternator came with a 4 gauge 6 foot long wire.

[vin63]

I run a #4 gauge welding cable from my 160 amp alternator to a positive battery junction at the rear of my truck (my battery is mounted on the frame under the bed behind the rear tire). I also run a Vintage Air AC system, but I also run an MSD Digital 6-Plus ignition, high-pressure electric fuel pump, dual electric fans at the radiator, and an electric fan trans cooler. You should be just fine running to the battery in the factory location.

Originally Posted by roll_the_dice

I just mentioned vintage air because that is who I got the alternator from when I bought their front runner system and A/C...in case anyone else had done the same.

But to your point, I don't think I have much load at all. The alternator came with a 4 gauge 6 foot long wire.

[roll_the_dice]

Originally Posted by vin63

I run a #4 gauge welding cable from my 160 amp alternator to a positive battery junction at the rear of my truck (my battery is mounted on the frame under the bed behind the rear tire). I also run a Vintage Air AC system, but I also run an MSD Digital 6-Plus ignition, high-pressure electric fuel pump, dual electric fans at the radiator, and an electric fan trans cooler. You should be just fine running to the battery in the factory location.

Thanks for the input. I do have an electric fan on my RND Fab radiator, but with a manual I don't need a fan trans cooler. I have a Fitech EFI system, but I don't think that pulls much juice and I do have a high pressure electric fuel pump. I think I will be fine with the 4 gauge I already have.