I wonder if he printed out an SAE corrected sheet. I've heard you can really play with the numbers on a Mustang Dyno to make them read in your favor. I'll put it this way I dyno'd on a Dyno Jet and got 313 rwhp and 325 rwtq with long tubes, o/r x pipe, steeda under drive pulleys, jlt and the 93 race tune from Doug at Bamachips, I don't think it is even possible to make the power that your dyno sheet says with just an intake and a tune. The catbacks aren't really going to account for anything. If I'm wrong, I'm wrong and maybe I need to have that guy tune my car, but I know Doug at Bamachips hasn't even found that kind of power in his own car yet and he's already swapped out the cams.