I'm not sure if this has been covered or not, but it seems that since rotaries have exhaust ports (similar to 2 strokes) why wouldn't it be benifitial to have expanded exhaust pipes? It seems that it helps a great deal with pulling exhaut out of 2 strokes, could it possibly work with a rotary as well? It would look pretty funny I guess to have 2 funny shaped pipes comming out of our engines, but if it would help in pulling exhaust out -

if you don't understand what I mean by the exhaust pipe expanding..

can anyone explain to me how/why it wouldn't work with our engines?

 

Those pipes might work as a Helmholtz resonator. And it might work if you get the right dimensions/frequency correct.

 

Divergent cone's are very benificial, you can see them in the megaphones on race exhausts. The divergent cone section imho is counterproductive on a rotary seeing as we allready have internal EGR problems, this will just compound them. Also the exhaust/intake overlap is early in the cycle as opposed to late in the cycle as in a two stroke. In a two stroke the divergent cone serves to cram a bit more mixture into the engine at the last second before ignition, on a rotary it would just cause reversion (esspecially without a reed valve)

 

Alright that makes since, thank guys!