i just installed my system today. i have 2 Re 15 Se's on a AQ1200. (1200 rms). when i turn up my volume and subs my lights still dim alot and sometimes my battery indicator will come on. I have done the big 3 in 0 guage wire. i only have stock alternator which is 135 amps and a duralast battery. i am wondering if i upgrade the battery will it help me for when i am driving the car? i know that the alternator is the main source of power so will a better battery actually make a difference? also what about a second battery in the rear?
I dont think a battery will really help you with that much of a voltage drop. The battery can only supply what the alternator feeds it.
Best case scenario you get a bigger battery and it starts with a full charge it may help for the first few minutes of each trip, but will go right back to the same old problem.
I would hit up the local alt shop and see about getting yours rewound for a higher output, or buying an ho alternator.