I have a 40 size Zero, a 60 size Sea Fury, and a 60 size Stuka. All of them needed nose weight to balance so don't let a heavier engine scare you off. I am using an FX46 in the Zero. Takes off and flies fast and furious! I have an FX60 in the Sea Fury, Takes off easily in about 50 feet and flys at a good clip. I have a TH 75 in the Stuka 60. Takes off in about 30 feet and flys very fast at 1/2 throttle! I usually throttle down to under 1/2 to keep the speed down. A 60 would have been plenty for it but the bigger engine doesn't hurt!