Personally, building an all motor rotary is even harder than the 6pt, due to the fact that the porting, exhaust, engine management setup/ tuning, and engine assembly would preferrably need to be done by the same person, and compliment each other in order to achive the most gains, which can get quite expensive.
More things for N/A all motor setup:
cooling mods
oil mods
rotor clearancing
rotor lightening
assembly ballance (rotors, e shaft, counterweights)
huge porting
new housings (not worth effort otherwise)
custom tuned exhaust setup
etc
etc
etc
otherwise why bother?
