Car Audio System powerful enough?

Right now I have a 220 HO alternator and a standard car battery. I have a Kenwood 8104D 1000w max and Crunch Powerone 600.4 amp. I was planning on putting another amp at 2000w max. I haven't done a Big 3 upgrade yet but plan on doing so. Would I need anything else like another battery or a better battery, or another alternator? I want to try to keep this as cheap as possible