Exhaust: Max.HP with Min.dB - how?

[NoHachi]

Nopes, the "resonance type muffler" should have read "reflection type muffler". I just didn't write that down on account of me being a moron.

Reflection mufflers have a series of baffles inside them that form a sort of rats maze. Nothing straight through about them. Truth is, straight through exhausts will have a difficult time bringing noise levels below 90dB.

Minimum number of bends, bends that are there preferably mandrel bent, single diameter front to back (no sudden jumps ANYWHERE in the system), about 2" piping. Minimum number of welds and other connections)

Flowspeeds are so low through the muffler that its restriction (if decently sized) can be neglected. Try out several types and choose the one that doesn't make you deaf in a year.