Oh yeah... no wonder I haven't been reaching my full RPM. I'm only running one set of pipes! Too bad the auction is over.
I actually saw something in JC Whitney which was a exhaust Y-adapter that had a cable coming from it. You could pull or push the cable to change the path of the exhaust. I thought of getting one for my old truck, having one way go through the muffler and the other straight out. It would have been sweet to pull up beside someone, pull the cable, blast straight-pipe in their ears. Would have been even sweeter to have it flaming but that's just too much trouble.