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.
--
"Porsche....and Nothing else matters"