Well if those are 450cc injectors from a 1g dsm you will need resistors or resistor pack. I have the resistor pack if you need it. If they are 450cc injectors from a 1g dsm you would need to change the o-rings to the 420 injector o-rings for them to fit in the fuel rail. Might as well tune the car once you put in the injectors, I would also suggest a sfmu if you don't have one because fmu 12:1 is if you'll be running stock injectors. No sense in tuning if your not done with you setup and you might drop in bigger injectors soon. You can tune now but heh fuel cut will haunt you and then you have to tune again once you swap your injectors. If you know how to tune then it doesn't matter if you tune now or after the injector install but if you don't then why pay twice?