it's really up to you if you keep it or switch back to stock. if you keep it, it would be easy to do a maf adjustment to bring in your fuel trims and cut timing. going back to stock will change how the car drives, and you would probably get bored with it. but that can also be fixed by changing the transmission shift settings. a 3.4" pulley sounds like it is too small for those mods, but you can just take out some timing advance to fix the kr.