That was with PDK and sport tires, which makes it much less than actual 15secs, this is more than twice the jump. Also when was the nurburgring's surface tarmac redone? between the 997.1CS and 997.2CS lap times?  

And the lower you go on the lap times, the closer they tend to get and the less differences there are between cars, so 13 secs in times above 8min for example is not the same as 13sec difference bellow 8min times. Each improvement with each generation should translate into less of a lap time drop, as it gets harder and harder to reach the physical limits. Dropping to 7:40 is huge, never has a Carrera facelift o model change matched the previous version's GT3 lap. That alone is what makes me hard to believe that lap time ofthe 991, the 991 "CarreraS" will be matching a "current 997.2 GT3" with sports suspension, more horsepower, better high speed aerodinamic stability, cup tires, etc.


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