ChuckGant
Well Known Member
I am a new owner of an RV-7 with an IO-360. I am a professional pilot, but new to constant speed props on piston engines. My RV is equipped with a Grand Rapids Technologies Horizon WS and EIS 4000 engine monitoring system. I have read everything I can find from John Deakin and Mike Busch about flying lean of peak and feel like I have a pretty good understanding of the process and the "red box".
However...
Everything I've read talks about leaning as you climb and leaning at cruise altitude above 8000', where you know you are producing less than 60% power. My question is, how do you lean when cruising around at lower altitudes, like 2000-6000'? From what I understand, once you are below 60% power, you can do anything you want with the mixture control without hurting the engine, but none of the articles detail how you know when you are below 60% power. Are you guys just using the generic charts that many have in there POHs, such as 22" at 2350 rpm? These seem a little generic and inaccurate for something as important as avoiding detonation. Or, are you just doing a "big pull" on the mixture until it runs rough and then richening it up a bit? How do you safely operate if you want to run at a higher power setting? Please enlighten me on the best way to manage mixture down low.
Thanks,
Chuck
However...
Everything I've read talks about leaning as you climb and leaning at cruise altitude above 8000', where you know you are producing less than 60% power. My question is, how do you lean when cruising around at lower altitudes, like 2000-6000'? From what I understand, once you are below 60% power, you can do anything you want with the mixture control without hurting the engine, but none of the articles detail how you know when you are below 60% power. Are you guys just using the generic charts that many have in there POHs, such as 22" at 2350 rpm? These seem a little generic and inaccurate for something as important as avoiding detonation. Or, are you just doing a "big pull" on the mixture until it runs rough and then richening it up a bit? How do you safely operate if you want to run at a higher power setting? Please enlighten me on the best way to manage mixture down low.
Thanks,
Chuck