You probably won't drop much lower than 11v since most head units will just power off down that low and possibly your car will stall as well. Very bad for your amps. I'd suggest a couple extra batteries to safely run 3KW 1 really ballsy one at least.
How much crank power would a good enough battery have to have? Can i just run one battery for everything in my car, to run 3k daily, i wont have the bass all the way up all the time obviously, the battery i have now has 1000 crank power, is that good?
Its not just the cranking power on the battery that matters. Its more important on its capacity and its recharge rate. 5 Series do have a nice large batt, but there is far better. I would make sure your Big 3 is done sufficiently, then just add another good, deep cycle batt, and run everything with 1/0 wire. You could maybe get away with one XS Power 3400, and replace your stock batt, but still, 3000 watts is no joke, especially if you are dropping that far on 2000. I remember when I was a noob, I actually used to drop into low 10s, which was very bad for my electrical and my amps. Your goal is to stay up in the 13s and 14s, no matter what you are running.
