There's no guarantee the Wankel will develop as the Piston engine has.. After trying all sorts of valving the Poppet valve has Proven superior, even for GAS FLOW. Two strokes are virtually GONE. II wouldn't Put Money into wankel development. Round holes are easier to seal., IF seals have to have changing angles and flat faces It's asking too much. Even loose Piston Barrell face rings. Mazda gave it a good shake A pilot mate of mine had 5 engines in his RX3 but he Loved it. They don't have a Lot of torque at Low revs either but with a supercharger the Output is sky High But I Guess the Life is less.. Fuel was cheap in those days. Nev