I'm flying mine witha Irvine .72 and it probably could be said that the Irvine flies the plane "scale like" meaning it could use some more power. I think a 90 2 stroke would be perfect for this plane power wise but I had to add alot of weight to the nose of the plane (over 10 oz's). You could probably go with something alot bigger than the 90 because of haoe tail heavy the plane is.