RE: OS 91 FX Tach readings
I got my OS 91 FX in a H9 Pulse XT 60. I bought it used with a MAS 13X* prop. I put a tach on it a couple weekends ago. I was
getting around 10500. I tried MAS 14X8 prop not to long after I got the plane. The plane spends most of the time around half throttle so I really don't see how making sure it hits the power band is so important.
I also had a YS 91 AC in a WM P51. I oringally had a MAS 15X8 prop to keep it under 9000. I eventually put a MAS 14X8 prop on it and I am getting around 9200 RPM sitting on the ground. I am sort of worried that during high rpm runs that the engine might overspeed and brake. Anyway, the plane wrecked and so the engine is sitting on the test stand at the moment. I am thinking avbout putting it in a Sportsman Aviation Waco 60.