@donour
I have a question.. I saw a large part of the AS Vettes were running the new Yokos... some saying they feel like Hoosiers.. Don't know if a joke, but have you any feedback on them? I see some different size options for the Elise front..
That's a good question and it's kind of a long story. For those who missed the backstory, The Yokohama A052 has been on the SCCA street tire exclusion list for a couple of years because the molded tread depth was too low. Additionally, sizing and performance was somewhat questionable. Yokohama released a new version in the spring of 2019 with an extra 32th of an inch of tread that put it over the threshold for SCCA street class and a bunch of people hailed it as the new tire-to-have. Not a lot of people ran it initially, although it made it's way on to some STR cars for tours. It wasn't really a new tire and many of us looked at it's roadcourse performance -- a known quantity -- and believed it wouldn't be a factor.
It seems that in august a few vocal drivers tested it and declared it the new hotness. "Drives like hoosiers" is just hyperbole. It's not really comparable to a hoosier A-series tire. They are sized big though. For ST classes, which have nominal width restrictions, it's probably the widest tire you can get. For street class this doesn't matter. The winners on the tire throughout the summer were only ST cars, which made sense to me and I never bought a set to test myself. I was tuning the car all the way up till the day before I left for the finale. I didn't have time to go through a whole test and setup routine for a new tire compound. That takes weeks. I had good setup sheets for the evora on RE71s and about a year of seat time on all national surfaces. Nobody had shown the tire to be good enough to justify switching.
Once people got to lincoln, it because a yok frenzy. First it was drivers who brought them as a backup. Then word got around they it was "definitely better" and emergency overnight orders and horse trading began. People were beg, borrowing, and stealing to get a set for their heat. The tires on the winning STU car were on an FS car the day before. SSC cars became STX because there were some yoks that fit. Many fast drivers decided they had to have the tire and arranged to get them. I'm convinced it was psychosomatic. Even if the tire _were_ better, switching your setup on the last day is a bad idea. Several times I have been told that if I were on yoks, then I would have won. That's wrong. If I were on yoks, my car would have been more unpredictable and I would have hit cones.
That being said, a bunch of really good drivers with multiple jackets have data showing that the yoks first run is magic and faster than anything else out there. The tires don't come back though. Once they are warm they settle to a plateau that is similar to the re71. That is probably good for a pro solo, but for nats I maintain that the right choice is a predictable tire on a well setup car that I could attack every run and execute a plan with. One important lesson that I took away from pro racing is this: it's not enough to build a fast car and fast driver, you have to deliver the performance at the critical moment with few mistakes.
donour