"Peter Dohm" wrote in message
...
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.


GO-300, GO-435, GO-480, etc. There are lots of geared flat aircraft
engines. Note that all of the ones I mentioned are sixes. Fours are
tougher and twins are about impossible. Gearbox design is pretty critical.
Also, all of these engines got a bad reputation from pilots who didn't know
how to fly them. You never want to unload the gears. Put them is an
unloaded situation and the gears will lash with each power pulse and quickly
eat the gearbox.

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )