Magnum Fuel Inj Without the Beer Barrel

SCT hand held tuner just allows you to simply load a calibration file into the factory ECM. That calibration is setup by the vender that sells you the hand held tuner box.
You supply them all the details of your engine, trans, vehicle weight, etc, and they build a file to optimize the fuel and timing, and shift points if applicable.
You cannot make these adjustments on your own with the SCT hand held tuner box.