Gear Ratio
- Thread starter CHB RON
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Even if someone reports the gear ratio in their CHB with that engine, I wouldn't base a prop purchase decision on that info. This was CHB from 30 or so years ago remember.
But you can easily figure the ratio with a phototach. Rev your engine up to about 1,000 rpm and measure the engine rpm and then without changing anything measure the prop shaft rpm. Divide the two to get the ratio.
David
But you can easily figure the ratio with a phototach. Rev your engine up to about 1,000 rpm and measure the engine rpm and then without changing anything measure the prop shaft rpm. Divide the two to get the ratio.
David
dhays
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That info may also be on the transmission somewhere.
Ski in NC
Technical Guru
It was a byproduct of getting counter rotation. Both engines and gears spun the same direction, and the bell shaped reduction units on the back of the gears had planetary gearsets for both reduction and to swap rotation. Apparently they could not get the gear tooth counts right for exact same ratios. Some ZF/Hurth boxes have the same issue. Can be annoying.
Not an issue if engines are counter rotating, but that creates annoyances of it's own.
Not an issue if engines are counter rotating, but that creates annoyances of it's own.
