I've driven a stock SL65. Butt dyno says it would take a C6Z stock for stock. Not sure about the ZR1 though.
SL65 feels like a freight train. Wicked sound from the V12.
I raced one a few times at a track rental last year. I think his best time was 11.9 @ 120 mph. I don't really see one beating a C6 Z stock for stock.
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