On Jan 27, 9:27*pm, Orval Fairbairn
wrote:
In article
,

*bildan wrote:
Take a look at this:
http://www.fairdiesel.co.uk/

A Diesel version of the cam engine! This engine was certificated (in
gasoline version) in 1946 and was tested in a Piper Arrow, IIRC, in the
1980s.

I saw one of these run at a fly-in in Southern California about that
time -- it had a 4-blade prop attached and sounded like a baby Merlin.

I do not know the results, but I have seen some engineering materials
analysis, which indicates that it pushes the stress limits of some major
components -- namely the main cam followers, which drive the pistons. I
would think that a Diesel version would place even higher stress on
these components than a gasoline version would.

The design is intriguing and would offer a very low frontal area and
incredible smoothness. I think that it would have to be water-cooled,
due to its compactness -- air-cooling would be next to impossible.

--
Remove _'s *from email address to talk to me.

One thing about the opposed piston configuration is that it spreads
the loads from one power stroke over two cam followers. If the power
ramps on the cams are very steep, maybe the loads could be minimized.
Ultimately, it's about how much torque you can ask it to produce.

One thing I like is the pistons can be held at TDC for the whole
injection interval. That removes one of the big issues for high RPM
diesels.