Running a new set of 225 RT660 tires on my GR86 with stock suspension. Did 1:55.x laps consistently at Sonoma Raceway throughout the day, despite the weather getting hotter in the afternoon. Meaning I could have done a better lap in Session 1. 

RT660 feels much gripper than SX2 thus overwhelmed my stock suspension a little bit. Car has bigger body roll in corners and the cambers (front 2.3 rear 1.5) are not enough to have an even tire wear. The shoulders of the front tires are pretty much worn after the day. Therefore I would suggest at least have stiffer suspension or/and more cambers if you want to run these tires.

With my DIY oil pressure logging tool, I logged the oil pressure data and found there were a few places on this track (right turns with crest) that made oil pressure dropped to as low as 20psi. This pattern is consistent with what we have found in Thunderhill West last week. See the video for detailed results.

Also attached the video clip in the end that I had a fun chasing lap with a 2022 BRZ that runs RaceComp coilovers and 245 RE71RS tires. Check out his perspective chasing from behind https://youtu.be/qG732jNtU8I