I am thinking about getting a cap. for my system. I am currently running a pionner HU, RF 851s amp, 2 12's, and 4 6.5's.

What exactly does it do? Help save your battery life? Keep your lights from dimming when your subs are hitting hard? Do you think i hsould get one since i am running 850 watts RMS to each sub?

If I am not mistaken they store extra power on hold for the system, so it is not constantly draining from the battery everytime your bass hits. This is what I know from what I have been told

A cap is just like a large battery, BUT they can discharge almost instantly. They come in handy for large systems, usually when you have multiple subs, and multiple large amps. The only drawback, is once they discharge, they don't do any good,until they recharge again. Caps don't make your alternator work less, or anything like that either, all the power has to come from somewhere, and its from the alternator. This is the biggest misconception with caps. IMO, if you are DB dragracing, and only "burping" the system for a high SPL score, then caps are a waste of money. If you want to spend your money wisely, then get a good, Optima yellow top battery. They can discharge much faster than a normal car battery, and also have a higher amperage output over a stock battery. Caps help slightly with dimming lights, but I noticed the best improvement with that was with installing the optima yellow top battery..

great thanks a lot, points for u

I second the yellow top :)

What about a Red Top? Thats what I have and my volts bounce back and forth with the bass hitting.