Pete, IMO all the listed engines are overkill. That airplane is very close to the Goldgerg Extra and Aeroworks 60-90 Edge, I have flown those both with OS 108 engines and they had great power to weight. The OS was heavy for its displacement. You may want to look for a YS 91 or 110. They are pumped engines so you can put the tank at CG and provide the best power to weight. They do have an undeserved reputation of being difficult to tune. They are different and you need to take the time to learn them. There is a weath of YS knowledge in the Scale racing forum here on RCU.