with the kit i you have to get a bigger fuel pump and bigger injectors....some people tell you dont have to but you do....i dont think the other guys were putting their car in the dyno which tells your the real air/fuel mixture and im running somewhat lean....the shop XAT Racing had to do some modification to the kit to make it fit....other then that everything is running great...the kit i got comes with a turbo timer and apex afc II