Good morning everyone. My name is Chris and I picked up one of these models last fall. I'd been wanting one for a long time, so when I saw it had returned to special order from discontinued I jumped on it and picked one up. I've been really enjoying building it so far. The airframe is 80% done, still need to pick up my radio gear and mount the engine. Which brings me to my question of the day.
I'm going to be running the big Saito 220 GK in mine. And yes, it'll fit nicely without modifying the firewall, there is about 1/4 or 3/8 inch between the carb and firewall when the spinner backplate is at the correct 6.25" distance. I want to build a custom Pitts style muffler closer to scale, but that's a different subject. In case you're wondering why I want so much power in the plane, there are a couple reasons. One is that I had the 220 already and would rather not buy another engine. The second and more important is that this is going to end up being a float plane, with a set of scratch built floats that will be as close to scale as I can make. Also, my experience with float installation is that they tend to push the CG back, requiring some nose weight to balance. I hate useless ballast. I'd rather use the extra weight to get more power, and have the extra power to deal with the floats and any other accessories I want to include.
I'm worried about the vibration of the engine though. I picked up a set of the DuBro anti-vibration mounts, but one of the mounting screws collides solidly with the mixture screw and throttle arm on the carb, rendering them useless. The included H9 mounts will work to hold the engine, but have no vibration damping and are frankly pathetically made. The Saito mount for the engine is also solid and would mount the engine too far forward.
I've been brainstorming alternatives to this that don't involve carving up the engine box, but short of having a set of custom mounts machined (which I love from an engineering perspective, but hate from a cost perspective), I'm not coming up with much. Has anyone with a larger single cylinder engine had vibration-induced problems? Any alternatives to help ease them down?