Alternator wiring upgrade/mod

I was just wondering how many people are running the upgraded/modified alternator wiring.

For those that don't know what I'm talking about, it's this:
- Connect 4 gauge cable from the alternator positive lead to the battery positive terminal.
- Connect 4 gauge cable from the A/C compressor mounting bolt to the battery negative terminal.
- Connect 4 gauge cable from the battery negative terminal to a new chassis ground (near the battery).

Apparently, it yields a better connection between the alternator and battery, and a better ground between battery and chassis. This, in some cases, increases the voltage that all of your accessories see.

I performed this mod on my car about a year ago, but not long after doing it I started to get the dash light "ghosting." This is when some of the lights on the dash start to just barely illuminate. I also noticed that each morning, my stereo head unit was reset. Shortly after this, my car would not start. I removed all the cables, and the car started just fine.

So, for whom is this mod working? And not working?

I'd love to get this upgraded wiring in my car, since I will soon be installing some powerful stereo equipment.

Thanks all!

[Earthworm]

I'm wondering if something was shorting in your installation. I don't know of anyone else who experienced problems after this upgrade.

Try just upgrading the ground wires and leave off the battery<-->alternator wire to see how the car handles that.

[immortal_suby]

One point to ponder. When the alternator was going in the wife's svx with no alternator wiring mod I swapped it into mine which has the wiring mod and the infamous dashlight christmas tree display never showed up in mine with the bad alternator.

[lee]

didn't vote because I never tested; however I have had no problems, so I'm in one of the first two categories I guess.

However, I can't urge strongly enough that you put a fuse (or fusible link) in the line between the alternator and the battery. The wire will have to be run over or under the A/C lines, etc. A bit of rubbing, and you have a shorted wire...alternately, get in an accident and have the front end stuffed - shorted wiring around potentially leaking gasoline, and....

BTW, I run an Xtant 603X amp fused at the recommended 100-amps. I run from the alt to the battery & at the same battery terminal, go right back to my stereo amp - so its more or less a straight run from alt to amp.

One last item. I think if you have fresh wiring (mine was cooked and the insulation cracking off inside that little rectangular wiring loom) and good grounds, the change will produce minimal (if any) advantage. But if the wires/connections are marginal, and the amp you're going to use has a big draw, then the 4-gauge run from the alternator to amp (with a slight stop at the battery) might save you a bit of voltage drop when the bass hits. This is for an unregulated amp though. Owners of regulated amps having decent capacitance for the power supply (JL, Xtant, some others) should expect to see little improvement (IMO).

[Chris]

I did it and found a 0.7 volt increase to my headlights. I have not had any problems.

[svxfiles]

Evan with the battery in the trunk, and a 4.25" crank pulley instead of the stock 5.25 pulley, and higher output headlights, it works fine. It has for a long time.

I got some higher quality cable and eye-terminals than the first time that I did this upgrade.

- Street Wire 4AWG blue multiple-thread cable
- Street Wire crimping eye terminals w/ shrink tubing

The terminals worked great, until I had to attach the negative ground cable to the A/C mounting bracket. The bolt was thicker than the 8mm hole in the terminal... So, I had to drill it out, which was quite a difficult thing to do - I didn't have a drill bit large enough, so I had to use one at multiple angles to increase the effective lateral size of the bit.

I measured the voltage with my multimeter before the install: 13.79 - 13.80 volts, with the car running of course. After the install: 14.20 - 14.22 volts. A 0.4 volt increase works for me!

The headlights don't really seem to visibly dim at idle anymore. They did it the most when the radiator fans would kick on, so I turned on the A/C to check them (this turns on the fans). The lights did not appear to dim.

I also have no ghosting in the instrument panel (yet). It took a while for it to do it before, but for some reason, this install just feels to be of a better quality.

The car used to start up with a crank-crank-crank-crank-vroom. It now sounds 1 to 2 "cranks" shorter.

Sweet!