here is a good wire site for some info:

Speaker Wire

my car came with a fairly high output oem stereo and had heavy duty stock speaker wires...16-18 awg, and heavy stranded wire, with very tough jacketing, so I used it. Resistance values and voltage drop were well within good ranges for the lengths used and power being applied. So, depending on the power applied and length, there's no reason not to use them...copper is copper.

 

Hmm when I install an amp, It will be all new wiring anyhow since the + & - have to go from the crossover to the amp correct?

 

not necessarily, one set of wires (+ and -) are run to the doors with the full range signal which is then split via the cross over (mounted in or on the door) to the separate tweet and mid, so you may already have a good set of wires run to your doors that you can use. However, I'm not saying you shouldn't run new wires, it depends on what you have from the factory and where it's located, as well as the power going to your speaks. In my case, all the wires from the 9 speaker oem system were run to the back of the car at the oem amp, were sufficient thickness, and were all located in places that I wanted to put my speakers anyway...sail panels, front door, centre channel, and rear door and deck. Truth be told it wasn't really easier to use the oem wires as I decided to use a molex connector to interface with the stock wiring harness. That way I didn't have to cut and splice and can easily return the car to stock, also, I can remove everything very quickly and easily if I need to. It was very time consuming to solder and crimp the little molex pins though...especially for 18 connections...4 tweets, 4 mids, 1 centre. Since the system is all active it worked out perfect. Most of my other cars have had all new wiring as it was needed.

 

Cool, thanks for the info dude .