yeah many have tuned themself, but u got to understand, u have to face the fact that practise makes perfect , if u tune urself without experience and knowledge , it will blow
things that i know tht u need to know
base map , ignition timing limits of your engine , engine knock reading, wideband sensor and logging , must know how to read lambda and afr , wht afr suitable for turbo , wht afr suitable to acceleration , wht afr suitable for n/a , experience of hearing engine sound to know if there are any problem or faulty , i would say its more to experience , i put my hands up in the sky and surrender , i cant tune cars :D