i guess i'll try a capacitator. how would i install another battery though?
Search bro, search! This should be a perfect example of what you want to do. From what I've been told 90% of the time a capacitor might help with dimming lights and such but they put a ton of strain on your alternator and can cause premature failure. I would go with a 2nd battery and that SHOULD solve any problem you have.
http://98.196.65.94/dual_battery.html