best thing to do is just add a second battery and run the amp off the 2nd battery. Provides more then enough power to really make your subs hit hard but at the same time wont drain down really fast compared to an cap. Ive been watching my friend mess around with his system and he has all top of the line everything, 2000w amp, the works. All running off his stock battery and now i believe he is on his 4th cap. I mean really if your gonna spend a lot of money to get a good cap, why not just add a 2nd battery and a bigger alternator down the line? In the long run its gonna end up being cheaper. Thats what im gonna do in spring, all accessories off 2nd battery (ps2, 360, amps, ect) and just lights, radio, and normal truck equipment off the main.