ORIGINAL: Enterprise6
I wonder what this motor on this airframe would be like.
http://www.valuehobby.com/airplanes/...k-540-arf.html
Seems with a 13x6 I could get in to the 8lb thrust range which would be borderline 3D territory. Not sure this model has the control throws needed to be a contender.
I crammed a OS GT22 into a H-9 Katana 50 which ended up weighing 7.5 lbs AUW so you would be in the mid 6s for that model.
Based on performance feedback from others reported earlier in this thread, for a 5 lb plane, the engine can produce thrust needed for 3D. Where it might get iffy is that you'll have to probably beef up the engine box to handle the vibration which will add weight. That seems to be a common need with small 3D planes designed for glow engines.