For autocross, hill climbs and time trials with a FF1600 it seems like Hoosier has been the only answer for years. I think we are the only ones still using the cantilevered rear tires in the R25B compound. Avon has more compound choices and special super soft hill climb tires for other classes but not us. Did Avon ever make a cantilevered rear tire for FF1600? With our wheel width restricted to 5.5 inches, there doesn't seem to be any avenue to experiment.