Just a tad rusty here, but (on a 2 rotor rotary), aren't the rotors, and shaft geared at 1:1,so at 1K rpm there are 2K exhaust pulsations?... Where as in a 2 cylinder 4 stroke would only have 500 pulsations per minute at 1K rpm idle?. EFI content is that this is in reference to O2 sampling. Cheers Bruce