They're using multiple tricks to get more air into the engine. Duh. The most obvious is the camshaft, and lofting. Better flowing heads would make them faster in every instance.
Strange statement for someone that seems to think PFM is what makes power. Minimum CSA is not a linear relationship. If the CSA of the SM was large enough, it wouldn't have gained power. Simple as that. No amount of PFM is going to change that.
You play word games. Invitation not accepted.