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    These are charts that I plotted to compare performance with different props.  I used a Props, Inc. 67 x 68 wood prop, a Felix Bi-Cambered 68 x 72 wood prop, and a Warp Drive three-blade ground adjustable carbon-fiber prop.  I settled on using the Warp Drive for now with a pitch setting of 17 mainly due to it running noticeably smoother than either wood prop, and very similar performance to the Felix prop which had been on for a couple of hundred hours.  Note that the Props, Inc. prop had a much higher equivalent pitch than the Felix, even though the stamped pitch and length is smaller.  You cannot compare those numbers from different manufacturers!

    These were run with the external Spintech muffler which costs something in drag, for sure, but removes a large radiant heat source from  the engine compartment.

    For the engineers among you, let it be known that these were taken in comparable OAT atmospheres, and were only as good as a single pilot with a voice recorder could do.  The purpose was just to compare what changing props accomplished.  The GPH is not calibrated, but I can say it is very close after refilling the tanks for the last 300 hours.

    I welcome any comments and questions to Bill@weslick.com  For starters, please let me know your theory concerning why max IAS was almost identical in this first chart even though the engine rpm varied almost 1000 rpm??  (I have my own theory, but what is yours?)

    A recent cruise data point to add with the 17 pitch Warp Drive is at 8500 MSL, 4 C, 5780 RPM, TAS 166 MPH, FF 7.87 GPH