This is my second season of racing, in my very first race in stock SC (17.5t limit). I was talking to a guy on the driver's stand he said he had a 13.5t motor and considered it stock and used it for the entire day. I think he was relevantly new to racing but he pitted with a guy that knew what he was doing.
Being new at the track and not wanting to create waves, I didn't say anything. The guy didn't finish in the top 3 anyway. My track is pretty laid back and never checks anyone's car. But it still sucks when people cheat or bend the rules so they have an advantage over the rest of the playing field.