Our stock alt is rated for 90 amps. Its more than enough to run 1000 watts on. I have 3 amps and about 2000 watts, and even a UDP. All is great. Just remember, the more stress you put on the alt, the shorter its lifespan will be. A high amp alt is def a worhty investment if your funds permit (400-600 bucks).

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)