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Old 06-25-2013, 05:50 AM
  #31  
MTK
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Default RE: O.S. GF40 4st gas


ORIGINAL: AeroFinn

Hi Mark

Are you sure about the Mejzlik? So is it really an 18x10 and not an 18x8? I'm asking as you got 7900 with Xoar 18x8 so a couple of hundreds rpm more with a same size CF prop is what you expect to see..
That's not a surprise really. XOARs are often higher loading than other props of same dia and pitch....BUT they don't produce any more thrust in my experience, just more noise from the tips

These numbers are300-400 rpm lower than you would get with the GT33 2 stroke..... Plus the GT33 will turn even more prop at surprisingly high rpm. My 33s turn 20x10.5 and 20.5x10 (apc props) at 7400on Avgas, 50:1 mix. Premium auto gas produces a bit more output but it's not necessary for most applications

It will be interesting to see what the 4 stroke engine can do after full break in. And you gotta love that 4 stroke sound.....