I have a Davis Roadster and I am looking to change the main power wire. Anyone have any advice what size is best to use? I have heard that too big is too big and too small is too small, so what size is good.

0 if you dont have to run it through the frame. If you use 0, you will never need a 16 volt battery. My american has a 2 guage, and barely cranks the car with a 12 volt.

I use 2/0, because it is accessible to me for cheap, as in free. I work in construction and the welding wire they dispose of I can have. I could get by with 1/0. There isnt that much difference other that the insulation is thicker on the 2/0. And yes, too small is bad, but the bigger the wire the less resistance, which is good.

quote:

Originally posted by 329L:
0 if you dont have to run it through the frame. If you use 0, you will never need a 16 volt battery. My american has a 2 guage, and barely cranks the car with a 12 volt.

This, and don’t forget about the grounds too. Makes a big difference in cranking speed.

1/0 WELDING cable, if not, 2/0 standard cable.

I use #1 flex-a-prene welding cable.

quote:

Originally posted by 183N:

quote:

Originally posted by 329L:
0 if you dont have to run it through the frame. If you use 0, you will never need a 16 volt battery. My american has a 2 guage, and barely cranks the car with a 12 volt.

This, and don’t forget about the grounds too. Makes a big difference in cranking speed.

^^^trip zip and dead tf on

Use the biggest thing you can get w/o getting stupid. I ran 1/0 because battery is in front of car and about 15' from the starter.

I run #4 welding cable and have had zero issues. Grounding is much more important, and your ground cable needs to be the same size or larger than the power cable, as it has to carry the same amount of amperage that the power cable does. Many will argue that you need giant cable, but you do not....although bigger won't hurt. #4 cable can carry continuously 150 amps over a distance of 100'. Nobody has that much battery cable in their car, regardless of type of car. Shorter distances results in higher capacity up to a point. I don't know of a single race vehicle that will have that much continuous amperage being used....most are going to be in the 25-50 amp range, MAX. Starting, most use gear reduction starters as well and amp draw is for short bursts isn't an issue....16v is the best upgrade you can do for your race car as well..but 12v works, is REQUIRES larger cable...I'll explain why later.....As I stated, the quality of your grounds is more important than running the largest cable you can find, and that is also where most people have the most issues...your chassis is a very poor ground and direct grounds are the best when you can. Aside from that, welding cable for a given size can carry more amperage than battery cable due to more wire strands within it, and is substantially more flexible/durable....

Just my $.02

2 gauge here from the battery to starter and then to the alternator. HOP starter/ Powermaster 150 amp alternator. I never charge my 12v battery at the track…. NEVER!!

So I have some car audio amp wire that was from my sons car audio system install. Still have about 20 ft of it, its 1/0 Gauge Copper Clad Aluminum CCA, would this work ?

quote:

Originally posted by SmokinChicken:
So I have some car audio amp wire that was from my sons car audio system install. Still have about 20 ft of it, its 1/0 Gauge Copper Clad Aluminum CCA, would this work ?

No that's junk unless you are running sound equipment like an amplifier.

Run either pure copper or annealed copper wire. The only difference is that the annealed is heat treated pure copper and that makes it more durable and flexible. So depending on how much bend you need to make the annealed may be better.

Ditto on what dashoe said, stay away from aluminum, it expands and contracts with the temperature. Will cause nothing but problems.

Big! Gotta disagree - this is what I've used on last 2 builds and couldn't be happier - Copper Clad Aluminium

[QUOTE]Originally posted by DragRaceResults:
Big! Gotta disagree - this is what I've used on last 2 builds and couldn't be happier - Copper Clad Aluminium


Copper Clad in those short runs would not be an issue, when you start to get longer runs then that's when those issues will start. 2/0 is too big in my opinion for drag racing. Even on cars with lots of electronics nitrous etc 1/0 is big enuff to carry all they need and more.

https://www.motortrend.com/how...0strands%20of%20wire.

quote:

Originally posted by Da Shoe:
Copper Clad in those short runs would not be an issue, when you start to get longer runs then that's when those issues will start.

I agree & you beat me to it!

2BKING

I'd never use copper clad aluminum wire in any automotive application, but that's just me. Just isn't worth the issues you can have. Battery cables I use welding wire exclusively. Anything else I generally use ptfe coated, fine strand copper wire. Much more expensive but more flexible and durable, and the ptfe insulation can be thinner as well.....which reminds me, I have to get new wire for my dragster since I'm going to rewire it this winter.....