Even if you have mild mods you still want a tune. these cars just run so much better with a tune whether you are stock or full blown raced out. Our cars, from my experience with mine, seem to have a decent amount of knock out of the box. A tune is going make your car healthy and save you gas. There are many more benefits as well. I wouldn't charge you to tune, because you would be driving your car and paying for the gas. I would just need money to open up your car on the software. You never know as time goes on you may want to do more and I don't mind helping if I have the time. Also if you need bigger parts put on my brother can always put them on. That would cost depending on what it is but he is very fair. I'm rebuilding a spare transmission right now so I may in the future be able to do that for some GP owners in the area.