Bumpin_Ack;
Yes, I think you need to match your amp GA. or possibly larger.
I believe the "Big 3" is the: 1.) Positive power cable from the alternator to the battery (Probably the most important) 2.) Ground cable from the battery 3.) Ground strap from the engine block/head to the body/frame of the car.
If I remember correctly, 8 AWG is only good for power and ground up to about 350 total watts of amps; 4 AWG is good up to 600 total watts; Above that, you might need to go with a 1/0 AWG setup. Better QUALITY cables is also important.
If you go to
http://www.sounddomain.com and look up their amp wiring install kits, check out how many watts each kit is rated at and compare that to what your running. Your main power and ground need to be as large or larger.
Think about this: If you went with a 4 AWG on your amps because they need it, and you only have 8 or 10 AWG from the alternator to the battery, then you have a bottle-neck in the power supply line. Same goes for the ground cables. If the resistance to your alternator is too high, the amps will **** the excess power they need from the battery when demand is high instead of the alternator.
If you need to make the lines bigger, then they need to be bigger all the way from the alternator, to battery, to amps, to ground; otherwise you wind up with a bottle-neck in the system.
EXAMPLE SETUP: 1.) 4 AWG main power and ground; alt to batt., batt. to amp distribution block, batt. to ground, and ground strap. 2.) 8 AWG from amp distribution block to amps, and amps to ground. (Amps not exceeding 350 watts ea.)
Later. //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif