Paul,
here are some photos of a local 5151 Mustang with a Suzuki/Geo engine.
The thing I noticed was that the engine mount didn't have any
triangulation. There is one piece of tubing connecting the right and
left sides of this mount, but I'm not real sure that the design is a
good one. The builder says that the engine is sufficient as a
cross-brace, but it is mounted with lord type mounts, and will allow a
bit of lateral movement. Would it be possible  for you or someone with
more experience than me to do a structural analysis of this mount? I can
provide more detailed photos if you'd like.

http://picasaweb.google.com/john.marzulli/EAA1440ProjectVisitLoehle5151

Brian Trubee

It is not just the lack of cross bracing.
Right up there with the worst motor mount designs I ever saw :)
You will need an FEA but I don't have that capability.

Paul Lamar ...No rotor no motor.

Actually, this looks like one of the more popular ("standard") mounts
for the Geo.

There is cross-bracing on the mount under the engine.  Add 4 mounts and
it's pretty solid.

Part of the problem with the Geo mounts is that the engine lubrication
path assumes that the cylinders aren't vertical, so the engine is set at
an angle.  You can see that in the pic of the right side.  This makes
the mount look more kludgy that it really is, especially with the tubing
contortions needed to provide a way to get to the oil filter and
accessory pack for maintenance.

The real lesson here is that, FWF, reciprosaurs are nowhere near as
elegant as rotaries.

Keith Wood

http://www.rotaryeng.net/motor.html

I could not disagree more Keith:)