The 9 cylinder 1820 and 1840 CID radials used on B-17's were geared
approximately 16:9. However, your point is well taken, and I also am
unable
to name any 4 or 6 cylinder engines that have stood the test of time with
reduction drives.


Continental GO-300 (Cessna 175).
Lycoming GO-435 (Navion).
--
Geoff
The Sea Hawk at Wow Way d0t Com
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