We do have a dyno from another 370Z owner that came here to have that exhaust put on, but you should know that he also had other supporting mods (i.e. intake/header/high flow cat). Also, it is on the computer attached to the dyno, and I'm unable to get to it right at this exact minute. As soon as I'm free, I'll grab that dyno for you and get it over to you.
And, what is your zip code? just so i can get a little more accurate quote for shipping on the exhaust.
Also, just to give you another option, AAM makes a full 2.5" exhaust for the 370Z. If you're interested, a link to a video of an owner showing off his new set up is posted below.
AAM HFC & Exhaust Video Clips