I've been lurking here for a while but now I need some advice on my car I just bought a 2006 GT mustang it has 117k Miles on it I joined this mustang club in my local area on facebook and a guy suggested that he could plug up his diablo tuner to my cars computer and run the program on it and add 45HP to my car he did it to his car which is also a GT of the same year and said the only thing I would have to change is just to put premium fuel in the car instead of regular

So my question is since I don't know much about cars or tuning them could this be very damaging to my cars engine?

 

The problem is that unless he returns any car that he has used the tuner on which is still running the tune from that Diablo back to stock, he can't use it on yours. It would currentl be locked to his vehicle. Second, if he did tune yours, then your stock tune would be in his Diablo and you'd be S.O.L. if you needed to return to stock and couldn't get your hands on it. Third, unless he's running the garbage canned tunes, you most likely couldn't use his custom tunes. Fourth, canned tunes may be good for about 15 RWHP. A good custom tune is good for about 20-25 RWHP.

He's on crack if he thinks that his tune is good for 45 RWHP. Also, I wouldn't trust him to TOUCH my car if he thinks he's doing you a favor loading his tunes.