Amp limits for wire

[xirforever]

I was just wondering what your opinions are on how many amps different guage wires can hold? Like how many amps do you think it would be safe to run through a zero guage wire? How about 1, 2, and 4 guage?

 

[Miles B]

What's the application? There aren't many places you will need the current carrying capabilities of a couple hundred amp zero gauge wire in a car. Often flexibility is more of a concern in these situations anyway.

 

[xirforever]

Well like for people who relocate their battery to the trunk, the alternator puts out about 100 amps and im thinking about getting the 175 amp alternator. Just wondering what is safe to carry these kind of currents. Not sure how many amps would run through the wire with the battery in the picture also, im no expert. Just wondering how many amps a 0, 1, 2, and 4 guage wires can safely carry in a car.

 

[Lextreme II]

The larger the better is all i can say. BMW M3 has 00

 

[Lambo]

xirfoever, have a look here it should answer any questions
http://www.powerstream.com/Wire_Size.htm

Regards
Lambo

 

[Miles B]

I see. I believe 0 is considered good for 200 amps, but I figure just hit it with 00 or 2 runs of 1 or 0 to be sure of as little voltage drop as possible.

Who knows how much the starter draws while cranking.. I'd hate to lose more voltage than is necessary...

 

[Lextreme II]

I ran an extra direct 0 gauge line from alternator to the battery and three groud wires to the frame....

 

[Lambo]

Milesb , i saw somewhere that the starter is rated at 2kw, ill try to dig up what current it draws. it has 35mm cross section windings not the normal 25 so sucks more juice.

Regards
Lambo

 

[MaxPower]

2kw starter!! Based on Power = V(Volts) x I(Current), then I = P/V = 2kw/12v = 166A <--?? lots of current.

 

[Miles B]

Yeah that sounds right. I wouldn't be surprised if it spikes a couple of times that for a few milliseconds right at the start. If you put a normal 350 CCA battery in, it has trouble turning the motor over with the lights on.

 

[Lextreme II]

I have 1100 CCA and the 0 gauge gets hot after few cranks. Try this place http://www.mcmaster.com/ and look for page 726 or part number 6948K76. Its $2.85 per/foot. You will need about 18 feet just to be save.