Al to answer your question Ultra is considered a radial class.. and typically we run after na 10/5 or after Outlaw 8.5.. the unfortunate thing is there is no place to test that will have radial prep.. I recently purchased 5.0 gears.. and a big book carburetor set up for the Q.. my goal has been a sub 1.20 60 foot.. I guess I will keep my pencil on the drawing board..