I was looking at a dyno sheet from my 12A, (2,292ccs) and I have 173.3 HP at 6,500 RPM. This is with an intake manifold for a car that is making best power at 9,400 RPM.
A very short compact intake that looks like the Racing Beat manifold. I was talking Daryl Drummond at Mid Ohio yesterday and he confirmed he had the 13B up to just over 300 HP at 9,100 RPM. A bit steep for aircraft use but it gives you an idea that maybe the deep concern over tuned lengths is maybe less important than some people think it is. These are bridge ported engines, but you do that with a drill press and a die grinder. The engine weighs a bit less when you get done, and you don't need a turbo to post the big HP numbers. My 12A is required by the rules to breath through two 38MM chokes. The 13B has two 44MM chokes. So each rotor housing gets one choke. I will send a PDF of the sheet as soon as my wife shows me how to do that. Don't laugh, she can build a rotary too. Lynn E. Hanover