ORIGINAL: Wings-RCU
I use the standard (Not the pitts style) inverted large volume muffler with the tips cut off. If any thing I gained RPM and have a much quieter engine. The internal diameter of the pipes Bission use on their inverted muffler and the standard Brison exhaust diverter are the same. You just need to cut the rolled tips off of the muffler.
Wings is right on this one. Lots more power with the tips cut off. I just used a disc sander to sand the swaged portion off. The light aluminum sands easily. I didn't have a band saw and I can't hacksaw anything straight

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