On Dec 14, 12:45 pm, Alan Baker wrote:
In article ,
clare at snyder.on.ca wrote:



On Thu, 13 Dec 2007 18:19:14 GMT, Alan Baker
wrote:

In article ,
Michael Henry wrote:

GTH wrote:
Michael Henry a écrit :

why isn't the Lycoming O-540 or the Continental O-520 an
inverted V?

They are derived from opposed engines, and the manufacturers thought
easier to retain the same cylinders and cylinder heads as their 4
cylinder counterparts.

OK so I just push my question back one generation: why is the O-360 not
an inverted V?

I'm asking more from a theoretical point of view. What is it that makes
the opposed configuration more attractive than the V configuration for
air-cooled engines? Likewise: what is it that makes the V configuration
more attractive than the opposed configuration for liquid-cooled engines?

There are new aircraft engine designs out the the Jabiru as an
air-cooled example and the Orenda as a liquid-cooled example. They
follow the same pattern that has become the norm.

There have been a number of aircooled inverted engines in the post WWII
period.

...and in the pre-WWII period! The deHavilland Gipsy Major being a
notable example.

I think one of the factors you're overlooking is vibration.

Certain engine configurations have less vibration due to the arrangement
of the reciprocating and revolving components:

A 90 degree V-8; a straight-6; ...

...and a flat-4.

A V-4 would have more vibration than a flat-4.

Yea, ever drive a Corsair V4? Even with a balance shaft they are not
smmoth.

Um, somebody check me, but didn't the Corvair come with only one engine:
a flat 6?

--
Alan Baker
Vancouver, British Columbia
"If you raise the ceiling four feet, move the fireplace from that wall
to that wall, you'll still only get the full stereophonic effect if you
sit in the bottom of that cupboard."

OK...."check" the spelling