With a lot of "sport" engines, the manufacturers dont go the extra "mile" to refine their engines for reasons I outlined earlier - ease of use, and fuel economy, and one I didnt mention before - cost. I've seen vast improvements in performance by modifying the port structure of an engine. I already have plans to buy a Jett engine for one of my airboats, though this thread was started to get an idea of what changes would do what to a run-of-the-mill sport engine. I know the exhaust system has a lot to do with performance, but thats not what this is about. Perhaps I'm going about learning more of the internal workings of glow engines in the wrong fashion. Also to note: I wouldn't be going about this to make a "sport" engine perform like a Jett. I know thats not reasonable nor realistic.

My shop teacher from high school always said "The easier an engine can breathe, the more power it will produce.". I was simply trying to understand how this principle could be applied to a small glow engine. Again, I am probably going about this in the wrong fashion.