I made a simple cockpit controlled one, the cockpit controlled part is critical I found. Going from high altitude cruising to a few hours later down lower and playing around doing multiple take offs etc., there was no one ground adjusted position that did the trick as the day progressed. Rotax 912 but similar needs to you, ski flying, and going from single digit temps to 30+, from easy cruising to working it hard, the ability to control the shutter from the cockpit is crucial. Using some aluminum angle and misc., I made a track (top and bottom) for a scrap piece of lexan, which is held open by a spring I found in my junk drawer. That is pulled across the cooler by a push/pull wire, like is used for cabin heat. The only catch is....to remember to open it back up when needed, it can be too effective if you aren't paying a bit of attention. It is also very handy for quicker warm ups after starting.
When full summer hits, the lexan is flexible enough to just flex it a bit and pop it out of the tracks, and I zip tie it out of the way, as even fully open it blocks just a bit of the cooler, just enough for me to want it out of the way when it's 80+ degrees.
Just saw the other post, the splat thing looks good, just plan on being able to totally get it out of the way once it warms up as it too reduces the flow even wide open. My way was cheaper though!
