I’ve been recently thinking if there’s any two rotors in those displacements. I never seen anything above a 13B that has a two rotor configuration, other than three or four rotors that are commonly available. In the future, I would like to find something unique and make more power while keeping maintenance low

 

The number of rotors are how we measure displacement. 2 rotors have 1.3 liters of displacement (13b), 3 rotors are closer to 2 liters (20b) and 4...2.6L (26B)
Therefore that's like asking if there are any 5.0 big blocks out there for a Mustang. Nope, they are all 5 liters.

Hope this helps.

 

Wow! I’ve actually never known that, considering the fact how I’ve been around people that do have rotaries. I’m fairly new to this community and I’m currently doing tons of research before I get my hands on a 93 RX7 in a couple of months. Thanks for clarifying! This website had taught me so many things outside of YouTube. It’s astounding!

 

Most common Mazda rotaries have been 2-rotors, the 3-rotor was a limited run and the 4-rotor was only for racing. Rotors have increased in size and displacement through the years.

1965 - 10A - 2-rotors - 491cc each
1970 - 12A - 2-rotors - 573cc each
1974 - 13B - 2-rotors - 654cc each

the 13B size rotor continued until the last rotary in the RX-8. Most builds today use this size mostly in 2-rotor configuration. 3, 4 even 6-rotor have been done. More rotors = less common = more cost.

 

Mazda had a 15A (90mm wide rotors on 10A/12A/13B architecture) that never saw production, as well as a 21A and 22A "big block" engine design that was a two rotor with a larger eccentricity. They made a few production quality 15As but only a couple prototypes of the 21A and 22A.

A and B have nothing to do with engine family, just which engine was first or second with a given displacement. There was a 13A, that had 70mm wide rotors like a 12A but a larger eccentricity. The 20B was also not the first of its displacement (13G was) and the 26B was not the first of its displacement (13J was). Now, where did the 13G and 13J get their names?

 

What, no Renesis or 16X?

 

Well, the Renesis is just a side-exhaust-port 13B and the 16X was a never produced prototype....

 

John Deere had a 5.8 liter single rotor, there is a NASA paper on it or something like that.

 

the 8C is um 830cc per rotor, although it didn't come to the US

 

They make a single rotor version of the 16x for the generators, at least I think it's based on the 16x.