Wasn't rev counter, as it was being data logged (pectel monitor with Uncle Tony operating it at the time), and data logging showed 7600 rpm, as did the peak recall on the SPA rev counter.

Tyres were new Michelin Pilot Sports, but i reckon this is were the theory and reality times are decided, the tyres, different tyre companies have different rolling radius' for the same sized tyre, and they don't match the theoretical rolling radius.