I know you want to run a Supertigre 90G. But most warbirds require the engine to run inverted if you want to save the cowl for looks. And the Supertigre hates to run inverted. Seen many people at the field have to hold the plane upside down just to start it then have problems with it loading up. I would spend the extra few bucks for a four stroke, like OS or Saito. Or you could just cut the cowl up but with that big head and large muffler that is a lot of cutting. Not saying it is bad either way, just thought you would want to know. Good luck with what ever you get. Warbirds are great to fly, I love them.

Mike