i have a 1,000 watt jl audio amp and 2 kicker 10 in L7's in a custom sealed box. i have full trunk space and the ability to add a car audio amp without losing any space. some people swore i had 2 ,15 in speakers and no trunk space. well anyway the car power system is stock with stock battery, and i get no dimming of the lights what so ever, the only thing that happens sometimes is the tach will drop a little and the rear view mirror would bend down. when and if the battery starts to dim the lights i will install another audio battery in the trunk. and oh yeh caps are useless and tend to destroy the alt quicker

 

quick update for anyone that may look to this thread for inofrmation or/and answers about the thread subject and other disccused subjects within the thread:

1.) 2nd battery placement- only place available for placement of extra batteries that can fit "comfortably" will be inside the car somewhere. Most likely the trunk or underneath the wheel well like i will be placing it. No room found under neath the car for battery placement nor in under the hood. Under the hood might be possible, but will be a tight squeeze if you fine a spot.

2.) gs stock electrical might be able to keep up with a 2000 watt load with a spare battery in the trunk. i didnt personally test this but from a lot of research and reading i found out it could be very likely. id suggest throwing a batt in the back with a run of 0 gauge and seeing if that works. if not then try upgrading the front one. if that doesnt work either, do big 3. if that doesnt either check all install procees and if not then finally go with a h/o alt.

3.) in my personal experience and in my specific situation it seems like my (Or our) GS' are very sensitive to voltage drops. In my gs with good electrical and 2000 watts running even if voltage isnt getting toooo low, the voltage change EASILY affects the car and ALL lights dim pretty bad.

4.) havnt tried a final solution, but i am assuming a battery in the back to aid in the buffer of huge power demand from one battery will do the trick. great electrical in place but voltage needs to be more steady or less drawn from the same source of power that the car uses. second battery might be the fix. will report later.

just some quick answers for anyone that might be interested or might need them down the road.

 

Use a solenoid with the second battery and dimming will go away, but electrical problem will not be solved.

and no its not a GS problem as for my car drops to 10.5v when pounding and I dont get dimming lights, well actually just a slight dim. And thats with our lil ol stock alternator and a completely incorrect set up electrical system lol