Test run .049 What makes a engine ..

Eric, your first vid is what indcates the engine being over compressed. If the engine is new, this is typical to how it would run. Put 1-2 head shims in and starting will become much easier. While the engine was hitting 19k plus, don't run the engine like that if your trying to fly the plane. It won't happen. If you did manage to get to the handle, the engine would instantly go overlean and sag or quit. You can somewhat achieve a run like the second vid if your running bladder pressure. However, this is also going to require a fairly high nitro content of 35% or 40% which will needle better and a small prop. My recommendation to add head shims will assist the engine run. Ken