Hi, all. I have an idea I want to try out for a muffler design on a single-cylinder engine (174.5 cc liquid cooled fuel injected scooter engine). My idea is to create as free-flowing a muffler as possible (lowest backpressure) while still making it as quiet as possible using the concept of destructive interference of the pressure pulses to smooth out the exhaust note. Other design priorities are that it be as small and light as possible, and have room for exhaust heat recovery that will be used to increase engine efficiency. Anyway, it would appear to me that creating a passage that is teardrop shaped, (essentially two teardrop shapes, one inside the other), and forcing exhaust gasses to follow the curve of those teardrop shapes from the pointed end to the blunt end would allow for maximum destructive interference (and hence attenuation) of the sound pulses. Imagine one teardrop shape inside another larger teardrop shape. The exhaust gasses are routed between the walls of these two teardrop shapes from the pointed to the blunt end, where the exhaust pulses meet head-on in a 360 degree collision to self-attenuate before the gasses go out the exhaust pipe at the blunt end of the outer teardrop shape. Sort of like a 3-D version of what muffler manufacturers do when they split then rejoin the exhaust stream to cause destructive interference sound cancellation using baffles, as seen in the "Sound Canceling" image here: http://cdn.exhaustvideos.com/wp-content/uploads/2010/12/muffler-design-types.jpg [Broken] Would this provide for maximum destructive attenuation of the exhaust gas pulses, or am I off on a completely wrong tangent? Is there any math that would show how effective (or ineffective) such a shape would be at destructive interference sound cancellation of exhaust pulses?