Here is some data that this group might be interested in.

I have always figured that the location of the air intake on the 912is is not in an ideal location in a cowled airplane. Putting the intake behind two air cooled cylinders definitely heats the air up some, but I wanted to get some data to know how much. My dad and I installed two thermocouples on the plane; one on the outside of the plane at the wing root and the other right in front of the air filter. I figured if the temperatures were 30 degrees above ambient, it might be worth putting in a cold air intake. They were over 70.

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Granted, this was only during climb out but that is when full power is needed. Cruise resulted in much lower temperatures. Doing a density altitude calculation my engine is performing as though it is almost a mile higher than the rest of the airplane. At this point it seemed like it was worth pursuing a cold air intake.

I installed the naca side duct that Kitfox sells. I originally installed this with skeet tubing and immediately knew this is not the long term solution.

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So I decided to make my own ducting. I 3D printed some parts out of PVA and tacked them together with super glue. Instead of doing fancy measurements, it was much easier to just trim the parts to length and then figure out the angle while holding the part up to the airplane.

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Once the PVA part was complete, I fiberglassed over it. Once the fiberglass was cured I threw the part in a bucket of water for a couple days. PVA is water soluble so after a few days I was left with just the fiberglass part. Below is a picture of the finished installation. Not Mike Patey worthy, but I'm happy how it turned out.

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So the moment of truth - What are the results? Without touching the prop and flying on days that are similar temperature and density altitude I am finding that my RPM is about 250 to 300 RPM more than what it was without the cold air intake. My climb out RPM is back in the yellow.