my 2 nephews raced at atco on sat. 11.11@127 for the Z06 and GT500 10.86@127 w/1.58 these guy's have been B/Shittin back and forth since Jan. about who's going to win.with more seat time (Z06) the vette would get better,my guess 11.0 with a good 60' so GT500 all the way.by the way,Z06 mods/tune/pipes/tires/ and the GT500 evo stage2 w/3.73's and dr's. all in all GREAT race and I loved the exitement.