Go to www.hemifevertuning.com. You purchase the tuner (like a code reader) with the software loaded. Plug it into OBDII port and follow on screen instructions. It saves original program and loads the one you select. You get three programs (based on octane for std tunes). Tuner downloads your VIN and can only be used on that vehicle. But you can change which tune you run, and he can also write a new tune when you get a cam or other mods that may alter characteristics.