Originally Posted by klarowe
Wrong. Factory wires are completely capable of handling the additional power from 90% of the amps out there. You MAY lose some signal quality, but it won't be anything that the human ear can pick up. The only time you need to worry about changing the wires are for competition or if the factory wiring is bad. I've seen plenty of competition vehicles that used factory wiring with no issues.
Stock wires are what 20ga? (not even going to get into quality and inflation)
Anything bigger than 50 watts is going to have a loss.
Using a 20ga instead of a 16ga will cost you 10% of your output to resistance.