Forgive me if I am beating a dead horse on this one, but can someone tell me why carbs can change jets (IT 9.1.3.D.1.a), but FI systems cannot change injectors? It kinda made sense at a time when modifying the ECU was also not allowed. However, w/the passing of IT 9.1.3.D.1.a.6, why is the 'no injector rule' still in place?