Why would you want to ruin a good airplane by over powering it so.A 4Star 40 flies just great with a good 2 stroke 40/46 on it,it will do any thing you want it to do and you won't be stressing the airframe .I have flown them for years with various 2stroke 40's and 46's and all have been great fliers that did just what they were supposed to do.That is my .02 worth