I went to the local track the other before the races started and I was in the pits and people around here are starting to cut their exhaust pipes / silencers in half and drilling the end cap back on it. Could someone tell me if they've every seen it or even heard of it, or what it does? thanks

 

I've seen a few of them done around here also. I cut a White Brother's Pro-Meg about 4 inches. Drastically improved top end, while killing lots of bottom end. That's pretty much the whole idea, more top end.

 

Thats what it does, that is cool. Thanks for the info.