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I used regular exhaust pipe to collect the stuff & direct it out from under the tarp (I keep it stored inside with the tarp on). That alone, quieted it some. There is just a lot of plain engine noise, that I doubt another muffler would cure. Also, I would be apprehensive about hanging a muffler on the maniflod alone, without good support, for fear that vibration would shake it apart. Pipe fittings are heavy too.