Ok, I am thinking of putting an underdrive pulley on my car that currently has ~600W of power going to the speakers. Currently I don't have a cap, but I know that if I do this it would probably be a good idea just for trying to save my electrical system. My question is, what size cap should I get, and no matter what size I do choose, will it get rid of all dimming of the lights? Thanks for all replies.

 

if you're running a 1 farad cap [~1000w] it should get rid of the dimming, a 1/2 farad will only hold until about 500w so you're gonna need 1 farad...b4 i got my cap, when my system was turned up, my gauges would dim, and my lights would dim, but i got a LA 1 farad cap and no more dimming
atw

 

Get your UDP and stick in a deent battery and a cap, that's what I did and I have had 0 problems so far. 1F per 1000w is rule of thumb.