---------------much snipping------------
This is the point. If you want to take advantage of technology like
electronic control, you have to design for complete redundancy if your
control system has a sudden potential failure mode. Not practical for
the homebuilder. The farm tractor technology engine can have its
components built with sufficient inherent robustness, or have a very
gradual failure mode, to provide the required safety without needing
duplicate systems, (like a crude but simple carb) or at least a minimal
level of redundancy.

I am a fan of auto conversions, but believe that those conversions to be
viable must be as close as possible to a traditional aircraft engine
from the standpoint of simplicity and overall design, and the Corvair
using a Stromberg aircraft carb and a dual primary points ignition comes
closest to fitting the bill of any conversion I have seen besides a
Great Plains VW. Now that the crankshaft strength issues are known and
a way forward is clear, the Corvair engine's potential is even better
than before as a conversion IMHO.

Cheers

John Kahn
Montreal

In general, I agree. I wish also to advocate that, in the event that a
purpose designed crank and case/front bearing assembly do not become
available, a rear drive assembly might also resolve the problem--although it
might weigh slightly more. Or may not?

Examples of the suggestion include the Greta Planes rear drive for VW and
their derivatives as well as Steve Wittmans designs for Formula-V and the
Buick/Olds V8s. I took a look and saw that the Wittman plans remain
available from Aircraft Spruce. I have a set of the V8 conversion plans
that I purchased while he was alive, and presume that the biggest problem in
using them on a different engine might be selection of the optimum drive
shaft diameter. The obvious advantage is that the original vibration
dampening components, which putatively have been thoroughly tested in and
for automotive service, remain intact.

Just my $0.02

Peter