So if I bring an ASP Corvette out, that's fine in modified?

But take the interior out of a yugo and it's a race car?

And what do either of these cars have in common with Howard's car?
Pax Numbers
Howard's car BM 0.960 x 60 sec course = 57.6
Scott's car EM 0.928 x 60 sec course = 55.68
Charles's car SM (Race car) 0.866 x 60 sec course = 51.96
Rob's new Mustang CP (Race car) 0.860 x 60 sec course = 51.6
SSP whatever (Mod class 1 legal) 0.865 x 60 sec course = 51.9
ASP Vette (Mod class 1 legal) 0.863 x 60 sec course = 51.78
BSP S2000 (Mod class 1 legal) 0.859 x 60 sec course = 51.54
CSP Miata (Mod class 2 legal) 0.857 x 60 sec course = 51.42
How does it make sense to put Charles car in R1 as opposed to M1? Especially if we are driving on street tires. So I have to drive about 9 seconds faster than Howard to keep up. (6.x for pax and 2 secs for street tires)
Please tell me Charles's car fits better with Howard's car vs. something like Chris Meier's car with a blower.
edit: Corrected Scott's car.