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Old 12-14-2012
groundhog groundhog is offline
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overpropped vs underpropped

I just had a new diesel engine installed, which seems to be working well.
I also have a max-prop propeller where you can change the pitch in 2 degree increments.

The target rpm at max throttle is apparently 3500-3600 for this engine according to the mechanic. I can make about 3260.

After signing off on the engine, and sending the warranty info to the mfr, the manufacturer is saying that I need to decrease pitch.

Doing the math from the prop manual, which reports about 7% rpm increase per degree, I would expect to be then underpropped, at about 3725?

What is the point? I can hit close to the target above and below the target rpm.
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