I suspect this information may be of interest to some. I recently performed static thrust testing of a rear induction 3W 150cc. The test was performed with the engine installed in an aircraft with proper cowling and ducting. The engine has been thoroughly broken in (+7 hours). This is running premium gasoline with 3W synthetic oil mixed 50:1. Also, the 3W ignition modules were replaced with CH ignition modules (long story, but the change was necessary), and the Walbro carb was replaced with a Tillotson carb. I tested 6 props to select the prop with the highest static thrust. The tail of the aircraft was tethered. Spliced inline with the tether was a load cell with voltage output to a data acquisition system. The engine was properly tuned and allowed to warm before performing the test on each prop. All tests were performed on the same day within about a 2 hour time frame. Listed below are the results of the thrust test.

Biela 32x12 55.9lbs @ 5200rpm
Fuchs Freestyle 32x12 51.8lbs @ 4890rpm
Fuchs 32x10 30.8lbs @ 5550rpm
Fuchs 33x10 48.9lbs @ 5400rpm
3W 31.5x8-14 65.4lbs @ 5760rpm
Vess 32A 51.5lbs @ 5500rpm

Also, TBM props website has some very useful information about prop/engine testing and prop selection.

nice info... what exhaust were you using. I am thinking of trying the fuchs 33x10 on my 150 with greeves exhaust. I have been using the mej.32x10 but i am looking for a "gear down prop". The mej 32x10 on my setup turns 5900 rpms any idea what your setup will turn the mej.?

Jeff

Oh yeah, no canisters. Due to very limited space, only headers were used (and they were even shortened about 1.5 inches). I ran 3W canisters on a test stand and saw about a 300-400 rpm increase, but did not thrust test with the canisters b/c of the space constraints preventing installation on the vehicle. I'm not sure about the Mej. I think the blade profile is similar to the Fuchs 32x10, enough so that you would probably see similar results. It was unusual to get such low thrust on the Fuchs 32x10, but I tested it twice with consistent results. The Mej. may be a bit better b/c the Fuchs is a very slender prop and I think the Mej. is a bit broader, and perhaps thicker.

I may be wrong here but I thougt that a DA 150 will give about 90 lbs thrust. The 40% planes usually have at least 2:1 thrust to weight ratio. Someone should enter those props and rpm's into Pe Rievers thrust calculator to see if they correspond.