Nitto drag Radials,do they suck?

[Ackbar00]

Just got my mustang together last weekend. Got a Eaton Diff with 31 spline axles, welded the axle tubes, svo cover. Also got megabite Jr upper and lower control arms. The lowers are set to the 85% hole. I have 4 lug 17-9 Cobra R rims with Nitto 275/40/17 Drag radils on them. They have some street time on them but not much. Anyway went to the track and set it at first with 15 psi, good burnout, launch at 3000Rpm. It killed the tires and 60 ft at 2.17. Next left the same pressure but launched at 2200RPM and 60 ft was a 1.97. Last pass dropped to 13 psi, Big burnout, launch at 2000RPM and get a 2.09 60 ft. I know these are not the best drag radials to get because the dont have much sidewall to them, but i expected a little more out of them. Does anyone have these Nittos on there car and if so what are you doing that i am not.