I gave up on it before for that very reason. Youll tune it in one season then the weather changes and your cars sitting there wondering what the hell you did to it. Youll start wasting gas for no reason, youll loose power, somtimes youll be shooting out smoke, sputtering... theres a whole list of things that can be problematic if youre not expierienced and you go and get a. Youd be better off just having somone do it for you. just send it off after youre done modding and have a basic street tune that matches your mods.