HMMMM, MY first plane was and still is a Global Right Flyer 60 w a Magnum 61 in it, I had just gotten rid of a 64 Ford Falcon w a 715 Hp. 502 cu. in. big block in it, do you see where this is going, the RF60 now has a OS 91 2 stroke in it , second plane is a Global KWIK FLY II w a Magnum 91 in it , there is no sub for cubic inches BUT there is throttle control.