Laptimes from R&T PCOTY-2021 should be replaced to the different track layout:
https://www.roadandtrack.com/reviews/a34671759/2021-performance-car-of-the-year/
"And in order to add in a little extra spice, we ran Lime Rock’s optional chicane in lieu of the fast uphill. This was partly for safety, as some of these cars would hit the uphill going fast enough to catch air. Cool to see, terrifying to experience, and a potential disaster in the waiting. We estimate this layout adds about two to three seconds to a lap time that runs the classic configuration."
"The Mini ran a 1:06.3 on track, about three seconds behind the lap time we clocked on the traditional track layout in warmer conditions earlier this year."
No way Corvette C7 could be faster than M8 by THAT much.