Sleeve Valve Engine Model

The sound of the engines at the Reno Air Races is truly incredible, but this year one in particular caught my attention. A Sea Fury flew past with its original Bristol Centaurus engine, and the sound was notably different than the other radials, very low and smooth. It turns out this is a sleeve valve engine, which explains the different sound. I figured it'd be a cool thing to make a model of.

Well, it turns out the Bristol Centaurus is not a simple engine (seriously, that's an understatement). However, during the search I came upon an alternate sleeve valve design used in radio control airplanes. This design is not only simpler than the Bristol Centaurus, but is actually simpler than any other 4-stroke piston engine I've seen: http://www.rcvengines.com/how-it-works.htm.

So, here is a fully printable, snap-together model of a 4-stroke engine that clearly demonstrates the four strokes: intake, compression, expansion and exhaust. What I'm most pleased with is that the tolerances a