Thanks! I was going to go with the Supercar F1 3, but they’ve been back-ordered in 305/30-19, and I’ve got a Sonoma track day coming up on 4/22 so I wound up pulling the trigger on the Kumhos. I’m definitely interested in the Supercar 3 for the next time I need tires…If you are a USAA member you might want to check out the Goodyear Eagle Supercar F1 3 or the even stickier 3R, as they give members a huge discount. Even if not a member that is another great choice as Kumho has been known over the decades to often run short on supply. They will wear faster than the Continental Extreme Force but they should not rub at a 305/30/19 size.
Sorry to hear the monoballs messed up your clearance as there are quite a few solid 315 choices along with the Conti Force.
The 3R sounds like a killer tire, but I don’t need that level of grip at this point, as I’m just trying to get better behind the wheel and can do that just as well at slower speeds/lower grip levels.