On Tue, 19 Feb 2008 21:16:53 -0500, "Morgans" wrote:

I intended to say that the PSRU ((_CAN_ )) be the weak link in an auto
conversion. Cooling, too, but you can generally tell you have a problem
with that, and deal with it without much catastrophic surprise.

You've actually nailed two of the three main areas where auto engine conversions
suffer reliability-wise vs. certified engines. The third is ignition system...
about 19% of the fixed-wing auto-engine failures involved the ignition, compared
to just 8% of the certified engines on fixed-wing homebuilts.

As far as "are auto engines strong enough internally for aircraft use," my
feeling is yes. The accident rates due to internal failures of the engines
(thrown rods, burned pistons, broken cranks, etc.) is just about the same as for
certified engines.

Ron Wanttaja