Have the 4400 HDR Black Death. I've got about 100hrs on her so far. I love the motor and it pushes my 17x50 w/hunt deck and all the gear for two guys with ease. My buddy's muffler cracked on his last week and it got me wondering when the time comes, should I put the Q muffler back on, or is there a muffler out there that would give me any benefits in performance. As far as the motor, I have done nothing to her, except take great care of it.... no add ons it is exactly the way she was when I bought her new. Thanks for any advice.

The more it will flow and give you performance, the louder it will be. I recommend the Voodoo for Max performance, then a SW is right under it with a little less noise.

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