I ran the 3R this weekend at Thunderhill Raceway. It was 90-100°F ambient all weekend. This was my first time ever with r-comp tires and it was the first time at Thunderhill with the M2. My car has -1.9° front camber with zero toe, stock rear alignment specs, Pagid RS29 pads, Castrol SRF fluid. TireRack heat cycled these before shipping them to me. Tires were 245/40/18 front abs 265/40/18 rear on 513M rims.
I found the 3Rs to be a bit "greasy" throughout the pressure range and they felt like a less precise RE71R. That being said, they are very progressive at losing grip and intuitive when they start allowing for time to correct as long as you're not overboard. I did 4 sessions each of the 2 days with total mileage around 190 over the 2 days. I think I have another day, maybe 2 at most on these. Looking at the wear pattern, I believe more camber would help these tires as you can see the outer edge wearing faster than the main tread face.
Overall, I am not so sure I would get these again. Will likely go back to SC3s once these are done, unless they turn out to be substantially quicker on my local track compared to the 3s.
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