Phase 3 chip?
 

Hey Ive been hearing that you can get these computer-upgrade chips that will increase your horsepower up to 25%. Does anyone know if any of these are compatible with the 2000+ Tiburons and where I could get one of these? Thanks

"Chips" or ECU Upgrades to not work on Stock Normally Aspirated cars to the tune of 25%. With turbo cars, they can turn up the boost, and thus increae the HP, but even on a turbo car 25% is a rather large increaes for just a chip.

There are no Chips or ECU upgrades available for North American Spec Tiburons.

Your best bet is to purchase an Apex-i S-AFC and have it Dyno tuned after you've done some mods. If you want to adjust your spark timing, the Apex-i ITC can take care of that, but again, it should be dyno tuned.