I'm heading back to the track this am for the two TA feature 75min races today. Yes they are fast, chatting with the corner flag man yesterday, and he stated "these drivers are crazy", meaning they don't back off for any flag he throws up.

To engine question, they look to be the typical SB nascar race motor.

One other observation, this the highest percentage of Mopars i have ever seen compete at a road race event, and they are not back markers, among a bunch of Mustangs, Camaros, Vettes.