I know that this query will raise some eyebrows regarding my actions and goal in making this prop pitch change, but it's a rainy day, and I needed a project.
History: I have 70 plus hours on the build now, and I have a pretty good feel for the present performance. On my first flight following the sign off, I found the prop to be a bit flat, and I was concerned about over-revving, so I increased the pitch, and it turned out a bit course. I now have a full throttle cruise of 5250, and although the speed are good, it doesn't take long for the oil temp to start climbing. Also, I would like to shorten my takeoff roll a bit, particularly when i have full fuel, and a passenger. All things point to the need to be a bit flatter. How much is the question.
Since I can't do it the suggested way of, making an adjustment, followed by a static performance test, and then to go fly, I plan to make a stab at it, and see just how close I can get. I'm thinking that one full degree flatter would do the trick. I did a search and found very little in actual documented experience, with real numbers, but from what I did find, it sounds like one degree flatter should get me close to a 200 to 250 rpm increase in full throttle performance. I'm just looking for another educated guess for now, because it looks like it will be several days before I can get an opportunity to test fly.
Tom
History: I have 70 plus hours on the build now, and I have a pretty good feel for the present performance. On my first flight following the sign off, I found the prop to be a bit flat, and I was concerned about over-revving, so I increased the pitch, and it turned out a bit course. I now have a full throttle cruise of 5250, and although the speed are good, it doesn't take long for the oil temp to start climbing. Also, I would like to shorten my takeoff roll a bit, particularly when i have full fuel, and a passenger. All things point to the need to be a bit flatter. How much is the question.
Since I can't do it the suggested way of, making an adjustment, followed by a static performance test, and then to go fly, I plan to make a stab at it, and see just how close I can get. I'm thinking that one full degree flatter would do the trick. I did a search and found very little in actual documented experience, with real numbers, but from what I did find, it sounds like one degree flatter should get me close to a 200 to 250 rpm increase in full throttle performance. I'm just looking for another educated guess for now, because it looks like it will be several days before I can get an opportunity to test fly.
Tom