Posted for "Kevin Stallard" <Kevin@arilabs.net>:

Mark,

I think the possible reasons people like Mike, myself and others stick
to certified engines is because they are well known. I'm not sure
reliability or fuel systems or moving parts is much of a motivating
factor to switch.

To explain what I mean: An airplane engine works in a different
environment than an automotive engine. The certified engines have
worked for a long time in this airborne environment. Someone (and maybe
this will be you) has to go through the efforts of really beating up an
engine in an airborne environment for a really long time with test data
before the aircraft industry and users will begin to "trust it".

Most folks who fly with certified engines get to know their engines
really well both trough training and experience and for the most part,
know what to expect. We just don't have any experience with the engine
you are speaking of so it gives pause to the idea of flying behind it.

I don't think there is any one in the room who would dismiss outright
your claims, however, proof is in the pudding so-to-speak, and until
someone goes through the effort and climbs that mountain, we at least
know what we have, and just knowing gives us options

I was just speaking to a friend of mine about the problem with the
IO-550 wherein turning on the high boost pump could kill the engine, I
mentioned that maybe I should put a pressure regulator on there so it
won't flood the engine. He being an engineer reminded me that I may be
introducing other problems by doing so and that I should be careful and
study it out well before taking any action. This is the problem with
non-certified engines, they don't have to function 100% if the time to
be safe, and therefore were developed under a different set of rules.

Did the engineers, make a trade-off or some other design decision that
will give you more problems than one of these old clunky certified jobs?
Who knows? But the only way to tell is through thorough testing and
beating the snot out of it.

But hey, this is why they call our birds experimental....I would love to
see your results after you have flown behind that motor for a few
thousand hours. There is one thing that the aviation industry needs and
that is change. I'd love to have a motor that didn't cost me $30k for
an overhaul or over $50k for a new one. But until I have the evidence
that there is a viable alternative, I think I'll fork over the
bucks...for now..

Kevin