Itsme:

Stupid question: what is he technical reason why rims on motorsport 911 are smaller (diameter) the on the street 911s? Reglement? Or any technical benefits?

Lower unsprung weight and quicker acceleration which a racing car does many times in one lap and in the course of a race. The trade-off is a lower top speed but acceleration is more relevant.


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"Porsche....and Nothing else matters"