it would probably have to go against D-stock.. right now if you were to race a 2 now, it would be in H-stock.. and comparing it with the Mini, not only its down on HP, but it's really down on the rear suspension to get the car to rotate.. the car wont last too long in H-Stock due to the fatigue of the torsion beam, not to mention uneven pavement.
I thought about it myself, but we'll see how 1 year of it in the WDCR region it will hold out. We have a lot of national champions here, but I'm only a regional champion for STS a couple of years back.
If the Mazdaspeed 2 revised the rear to something like multi-link somehow and disc brakes instead of heavy drums, then it might have a chance (assuming the motor can put out 180 whp, or 200 hp at the motor).
Wouldn't it be classed against the regular Cooper instead of the S? They both have similar acceleration figures in stock trim. (I've timed both in AT form). I think it can be made to perform... from a short autocross drive in the sedan a few months back... very easy to rotate the longer sedan compared to the hatch... but it may just be a question of creative alignment tuning.
Would they assign it a weight penalty, though, for being lighter? Not quite up-to-date with US racing regs.