Originally Posted by devo
I don't believe that BMW is cheating either. Comparative tests should be conducted on the same type tire; that's all. Any other test is unfair.
You are right, most late model cars have run the Ring on CUP tires. The 911S has not.
The 997S might not have been running CUP tyres but I believe it was using Ceramic brakes.
In any case I feel all tests should be conducted with a few choices, in the case of the M3 we should be able to see the difference in times with 18" and 19" options and what ever tyre options are available, same goes for the other manufacturers.
The only think I do know is that different tyres options like the difference between 18" and 19" or UHP and UHP+ will effect the way the car behaves and it's not necessarily the quickest option that is the most enjoyable one to own and live with.