So, I just ran about 1/2 tank through the "Bat" pipe. I am running it on a Jammin JPX .21, which is the mill I will have for Truggy @ MotoRama (will be running ET's in my buggy for the summer ) Anyway, all I can say is...WOW! Now, granted, I havn't had it on a track yet, so I can't say right now what it will be like in racing form...but just beating around in my back yard, there's a huge difference compared to the JP3 I had on it. Nice low burbling idle, bottom is solid, SICK mid range to top. All in all, I think Im gonna really like this exhaust and can not wait 'til Friday to practice on track!