The biggest difference is the torque curve between a 4 stroke and.2 strokes, 4 strokeshave a much higher torque curve ,at a lower rpm, where as a 2 stroke develops it torque at thehigher rpm,s
A 46 ax has more power then a Saito .56 but only when the rpm,s are way up , drop the rpm,s down to mid range and the .56 will out pull it.