RRs are slightly (about half a second) faster than both RC1 and AR1 tires at Streets of Willow (1:20 long track) on Supermiata's test. Same sizes same test environment same driver. It makes sense since AR1s are only slightly faster than the tires like NT01 and R888Rs in 100 tw tire category ..hybrid R comps.
RRs on the other hand is slightly more aggressive than them (similar to Cup2 , Trofeo Rs) maybe. I chose the 315/30/18" RRs for 18" sizes,. I also heard they (AR1s ) also heat cycle out whereas NT01s or R888Rs don't. According to the testers RRs also last the longest out of the three
https://www.ft86club.com/forums/showthread.php?t=135222
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