BillL
Well Known Member
When installing my SJ cowl, I had some question about the pressure drop of the conical filter [K&N E-0995]. Doing measurements of the pleats and calculating the surface area indicated that it was comparable with the flat rectangular filter DanH tested in his thread on the shrinking exit. It was somewhat correlated with the amount of oil recommended by K&N after cleaning. (yes, that is a stretch)
Today, I tested the system at several RPM and the maximum pressure drop was 2.2-2.6 inches of water. I have an IO-360, so that seems pretty good to me.
Attached are some pictures of the ports and pressure dampers made for the test. damping volumes had a .040" orifice on both ends just to be sure. And . . . it worked quite well, the most stable readings I have gotten with this device.
Pressure recovery from airspeed was really good too, but that is a different story.
Today, I tested the system at several RPM and the maximum pressure drop was 2.2-2.6 inches of water. I have an IO-360, so that seems pretty good to me.
Attached are some pictures of the ports and pressure dampers made for the test. damping volumes had a .040" orifice on both ends just to be sure. And . . . it worked quite well, the most stable readings I have gotten with this device.
Pressure recovery from airspeed was really good too, but that is a different story.
