Gentlemen,
    I am building an acro rated single seat biplane that the designer has limited the max. engine size to IO-360. I am surmising that this engine limitation is based on weight and airframe maximum speed. I have decided to use rotary power and am slowly developing a plan as to what I will use. I am looking for a little more help going "vertical." The rotary weight (less) will be a bonus. I am not an engineer and am not even related to one so my question:
    Can I go to a P-port 2 rotor in the 230-240 hp range if I do not exceed the max. airframe speed.
Thank you,
Randy