I don’t know how well that Sato engine will fit on the Slowpoke ARF. I put a Magnum 52 4-stroke on mine, but the carburetor hit the fire wall, so I sloped it back to make it Magnum fit. It turned out very well, as you can see. I haven’t flown it yet, but I just thought you should know what the engine fit may be a problem w/ the ARF. I would love to know how that turned out w/ the Sato. I emailed Great Planes about it and they said that all there planes were designed around OS engines. Good luck!