Join Date: Mar 2002
Location: Austin, TX, USA
Proper wire sizes is a tricky topic. At least as far as any official rating of "use this size wire for this much current" does not exist. Wire is rated in resistance per foot. And knowing how much resistance you can tolerate is just a small part of the equation. You need to know the maximum voltage drop you can afford to see and the maximum power you can expect the wire to dissapate.
I did find a chart that lists the temperature rise per amp of several wire sizes. I think it's a pretty good guide if you consider the maximum temperature rise you'd expect the wire to see. I'll try and locate it. It works pretty well if you consider the load current, length of the run and other basic aspects of the circuit.
68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI