Yes as chase said, most ppl do run 17.5 and the track, but it is a open class at our track, so mod motor cars are more then welcome to race. I run a 13.5t in my b4.2, and am normally in the top 5, but hardly get the win against the 17.5 cars. Its very close racing on this track. I encourage ppl to show up and race no matter what they are running. I dont think there would be anyone that makes a big deal over getting beat by a mod motor, we would just be happy to see some new drivers at the track.