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Can anyone recommend an airframe for an O.S. FS-70 Surpass?


New to GSN!
I have an O.S. FS-70 Surpass four stroke engine I bought back in 2003. I would like to move this into a nice 3D capable plane. I have been having trouble finding a suitable airframe to put this in. So many out there seem to be setup for electric.

Can you modify an electric to take gas? I've been building since 1990 so I wouldn't mind doing a mod. - or even a kit build for that matter.

Any suggestions?


70cc twin V2
It should spin a 13" prop at about 10,000-11,000RPM if you use quite high nitro fuel (expensive!). I'm guessing about 7-8lb of thrust, it's not really ideal for a 3D plane because the prop is a bit small, two stroke gas engines tend to rev slower but have more torque to spin bigger props. The surpass may be ok for something in the mid 50's" span range. It's probably roughly inequivalent to a 1100W electric set up.
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The next problem is that the airframes in the 50-something inch range are almost exclusively built for electric power and aren't designed to withstand the vibrations of a glow motor. To be honest, you're probably better off scrapping the idea and going with an electric setup. Motors in that range will range from about $30 bucks for acceptable quality stuff to about $100 for the very best ones. ESCs will run about $50 for a good one (e.g. ZTW or HobbyWing) to $100 for the premium brands. With that in mind, it doesn't really feel it's worth the effort to try to build something around your motor.

Now, that being said, if you're doing it because you like to tinker, it's a totally different story. You'd probably be able to power something like a 51" AJ Slick on that, but you'd have to pretty much rebuild the entire motor box.