i have a 2000 grand am gt, with two alpine type r 12's, custom ported box, 0 gauge wiring, 200 amp fuse, 120 dollar pioneer head unit and also the kicker zx 1500.1. stock alt and regular battery and runs fine. no point of mirrors in my car, trunk is loud as shit which means SLAMMING. hopefully this answers your question lol
http://www.youtube.com/user/skater041930
and look on this site to order, cheap prices great quality, never had a problem with any thing (only got subs and amp from site)