Broke unless i've got my numbers f**ked up , the best Vette cost in the area of 70-80,000, and I may be wrong but I think theirs 3 American sport car with numbers faster that the vette. The 2004 Ford Shelby Cobra, The Viper SRT10 and the Ford GT40. But let's not leave out the much cheaper by almost $40,000 the Ford Mustang Cobra SVT, very close but not really a sport car.
So unless I'm missing something please post something
2004 Ford Shelby Cobra 2.8 10.6
2004 Viper SRT 10 3.9 11.7
2004 Vette 4.3 12.7
2004 Mustang Cobra SVT 4.6 12.9
and the GT 40 well blow all their doors off I think
Myself I like my Z's and haven't yet been beat by a Vette or Mustang, but I know there's one out there someplace waiting to prove me wrong. As for the other 2, never had the chance to try one.
Lov your tire statment
http://www.ssmoparmuscle.com/speedcomp.htm
http://www.gearheadracing.com/Reference/FordGT40.htm