Originally Posted by
CristianTabush
From my understanding it is because asphalt and carpet are a different surface. If Knapp has not won an asphalt nat, then he is ok to run 17.5.
I don't know if Knapp has won any 17.5 asphalt nats though.
2012 1/12th Asphalt 17.5 champ -
http://www.roarracing.com/results/na...ls_Results.pdf