nberry:
I'm sure tires played a role but let's give credit to the car. AP said the RS was a scalpel and he's right. See how well the car straighten out the curves and turns. Sure the driver had something to do with it but the car is the star.
FWIW, I seriously doubt the 918, GT2RS or the GT3.1RS would have similar improvements in time. I suspect Porsche in designing the .2GT3RS did it with this tires in mind.
Tires actually play a bigger role on the 918 than anything else.
It has more than enough power, performance of the car is limited by grip level, it's lacking aero grip too but one can't do anything about it.
GT3RS, has plenty of grip with respect to the power output, downforce is plenty in both the GT3RS and the GT2RS, but the GT2RS on the other hand has power to spare.
GT3RS is also lighter than the GT2RS os it is more nimble too in directional changes.
Sort of 3 different cars, but 2 different basic architect, all did under 7mins in different ways.
918 by brut force, GT3RS by agility, i.e. scalpel per AP, GT2RS is somewhere between the 2, sort of combining both attributes.
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