Credit to CorvetteBlogger:
[SPIED] C8 Corvette Z06 Prototype Confirmed Wearing 21-Inch 345/25ZR Rear Tires - Corvette: Sales, News & Lifestyle
While its been rumored previously, we can now confirm that the C8 Corvette Z06 will be wearing rear 21-inch Michelins that are sized 345/25ZR
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