ORIGINAL: bob27s

Nice setup... should work ok.....

Sure, I am always interested in data and information.

Static thrust means only a little, but it is interesting to see sometimes.

Be sure to include all of the variables if possible ..... location, temperature, RH if possible, prop, fuel, and the pipe length. (glow plug to the fat part weld).

Of note, the pipe will tend to keep the rpm fairly consistant, somewhat regardless of the prop. It tends to work like a governor as it attempts to stabilize the system at its natural frequency. Your experiment here may lend some evidence to that aspect. It will be interesting to see.