PaulaJay1 wrote:

What do the letters/numbers after the O 360 mean?

Lycoming has this to say -- "To determine the minor differences in an engine model
which are reflected in the model code suffix, it is necessary to consult the engine
specification. Most aircraft owners or pilots will have no need for this type of
detail."

In general, 1) the first character can be used to look up the horsepower rating. 2)
if the second character is a letter, it's part of the HP rating code and the third
character identifies the nose section type. 3) if the second character is a number,
it can be used to identify the nose section type. 4) the next character identifies
the accessory section type. 5) the next character (if present) usually identifies
the counterweight type. If a "D" follows this, the engine has two magnetos in a
single housing.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.