KresoF1:

There is a huge mistake in the list above and that is sem R tires. There is NO semi R tires and calling Michelin Sport Cup tire a semi R is a lie. Cups are closer to true slicks then Pirelli Corsas for example. Audi tested both Corsas and Cups in the same size on R8 V10 mules and Cups were about 3s faster on the Ring and constantly faster on all tracks.

Porsche is using most sporty Cup version for 997.2 GT2 and GT3 models, while for example on BMW M3 you can spec more mild Cup+ version. 

Michelin Pilot Sport Cup(as on 997.2 GT2)


If the tyres used on the Porsche cars are Porsche approved N-rated tyres then this is fair enough, because they are the factory approved Cup tyres.  If they did the laps with non OE tyres of a higher grade  that give better performance, then this would have been irregular.

If BMW for example, use milder tyres then this might be because their cars are not suited (for a variety of reasons) to the sportier version, so they have to suffer any handicap that emanates from this.

Additionally, 997.1 carrera could not be specified with Cup tyres from the factory because of possible oil starvation risk due to its simple lubrication system. So if someone shows a time with non factory approved tyres this would be irregular. This has been solved on the 997.2 with its better lubrication technology and Cup tyres can be ordered through Tequipment.

However, Iam not sure if the OE Cup tyres on the GT3 are the exactly the same as the Tequipment Cup tyres for the 997.2. Have you checked that?




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