Conditions were pretty volatile at Nats this year and they had a wager on who would get the fastest wet lap on day two (think it was the Focus RS). M2 winning PRO was probably a better gauge... beating Heitkotter and AWD cars with launch control and a drag start is damn impressive. But classes may change and new cars may shake things up next year.
Looks like APEX EC7s on 27/87/89, and stock wheels on 76/66 according to the below link.
Pictures from 2018 National Championships:
Pictures from 2017 National Championships