So I went to the track, and found these exhaust mods I've never seen before. What the hell?

Ok... why? The top and bottom cars use hardware store ducting.... for the easy redirection of the exhaust... but why?

The general consensus is that the exhaust noise is directed away from the sound monitoring device on the track so that the cars that are too loud to race squeak by without getting tossed out of competition for exceeding the dB limit.

Jack confirms it's to cheat the noise limit of 93dB, he was there this weekend

Thanks to all of you that commented!