low voltage!
Cargo Master
Joined: Apr 2004
Posts: 2,574
Likes: 4
From: Golden, CO
Hmmm, Larry, sometimes bigger is better. If you get the opportunity for a junkyard expedition, look under the back seat of an 80's Audi. You should find a battery tray with a big wire going to the engine bay. I don't remember the exact size, maybe a #1, or #0 AWG. As mentioned with welding wire, I remember it being a fine-strand cable. 
As for the rest of you, if EVERYTHING was on at once, how many amps would the system want?
Do an electrical audit, you'll be amazed at what different accessories consume:
Electric fans are power hogs, fan relays are my favorite to pluck at the J-Y. Usually, I wind up with a 60 amp relay when I get there first. There's half your peak output right there Greg.
Then there is the thing with wire sizing. Even if you do manage to move huge amounts of current through a smallish wire, it's will heat the wire and increase resistance. Then you suffer a greater voltage drop across that conductor.
If nobody beats me too it, I'll search out some wire sizing charts. I'll be on a trail ride tomorrow, so don't look for much before then.
g'night all
As for the rest of you, if EVERYTHING was on at once, how many amps would the system want?
Do an electrical audit, you'll be amazed at what different accessories consume:
Electric fans are power hogs, fan relays are my favorite to pluck at the J-Y. Usually, I wind up with a 60 amp relay when I get there first. There's half your peak output right there Greg.
Then there is the thing with wire sizing. Even if you do manage to move huge amounts of current through a smallish wire, it's will heat the wire and increase resistance. Then you suffer a greater voltage drop across that conductor.
If nobody beats me too it, I'll search out some wire sizing charts. I'll be on a trail ride tomorrow, so don't look for much before then.
g'night all
Fleet Mechanic
Joined: Aug 2007
Posts: 1,828
Likes: 253
From: Piney Woods of East Texas
If your load is such that your have a voltage drop yes. It all depends on what your electrical requirements are. With nothing but lights to pull current you don't need much more than the factory #8. But soon as you add a AC Clutch you just doubled your requirements. Then add electric cooling fans and your almost up to 100amps. So a #6 or #8 is needed. Provided you only have the factory rated alternator 55amp. Soon as you jump to a 100amp alt I would use a min of 3 #8 or a #2 or even a 1-0 welding cable if you have it. Most prefer to using multiple #8 or #6's depending on what they have access to. Using the smaller cables are a little easier to run in a wire looms, and terminate easier. Welding cables use a super fine wire for flexability and are easy to route and work with. On these heavy cables I always solder them after I do the crimp, this keeps the corrosion to a minimum.
