teh pros to having 2 alts. is to power some amps.... I remember back in teh day when In came by an amp I liked alot phoenix gold 2250 came w/: 0 gauge wire, fuse block, and a second alt. jus for the amp. I loved that amp 2610 watts of pure bass'n evil..... wut to do wut to do..... Booom Booom Booom