One reason why I would trade my 993TT for a 997TT:
http://www.dpccars.com/car-movies/12...rvette-Zo6.htm

 

Well, with Kevin's Stage 1 upgrade, I can pretty much hang with a Z06. No need to spend $140K to hang with the Z!

 

Problem when you get into this is the fact that the Z06 is also easy to mod (and cheap...). The Z06 is probably a little harder to launch... Notice, the guy shaved .4 secs on its second 1/4 mile run.
I've seen 11.7 sec 1/4 miles with the Z06 (in magazines...). I think Z06 and 997TT are pretty close in term of acceleration and pure performance but I would buy the Porsche (for looks and feel reasons) ...

Pierre

 

I love P-cars but a guy with a C6 Z06 has already ran a 10.85 on street tires (cheater slicks). It took him 52 or 56 passes I believe. The 997 TT is no match in acceleration compared to the new C6 Z06 in terms of quarter-mile. The guy is on a Corvette forum, I dont know which though, he logged every run and posted.

 

Best thing to do is keep you 993TT's and get the Z06; about the same cost as trading the 993TT for a 997TT. If you can't beat em join em.