Yes, the 'new' Kumho tire is not going to be legal until after Topeka.
Although realistically the new tire from Kumho is not going to be enough for the Z-06 cars anyways. It would compliment a LS1 Car very nicely, due to LS1 models, having taller gears, and 9.5" rears.
The tire from Kumho is a 285/30/18 and will match well with a 255/40/17 Front.
However... On a Z-06... the 285/30/18 has a lower overall diameter than the 275/40/17 Fronts. /phpBB/images/smiles/icon_eek.gif
For Z-06 Owners that want to run Kumho's I would recommend the new 335/35/17 which fits a 17X12" wheel Nicely. (albeit, you wouldn't be in Stock Class, but a lot of Z-06 guys don't run in stock. You could then run the 285/30/18's in the front!)
I was able to do some testing with the new Kumho, and they are much better, and Lighter ,however... the 18" is 'loose' on the 10.5" rear wheel of a Z-06.
Peace,
Dave
PS... I am on Kumho's for Topeka, although.. just thr Front! Like I have ran all year! /phpBB/images/smiles/icon_biggrin.gif
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Dave Schotz
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