I think Jason Heffner ran 11.5x in his 99-00 GTS, didn't he? I think Jamie Furman has run in the 11.6x's?
As for MPH, I dunno.... I have run 121mph in mine (121.1mph) was the best but my car was highly modified with K&Ns, smoothies, and the muffler swapped out for a straight 2.25" pipe that was non-mandrel bent with dents in it /images/graemlins/smile.gif I just say that as a joke - the car made 414RWHP and 465RWTQ so it wasn't a particularly strong Viper or anything.
As for MPH, I dunno.... I have run 121mph in mine (121.1mph) was the best but my car was highly modified with K&Ns, smoothies, and the muffler swapped out for a straight 2.25" pipe that was non-mandrel bent with dents in it /images/graemlins/smile.gif I just say that as a joke - the car made 414RWHP and 465RWTQ so it wasn't a particularly strong Viper or anything.