wrote:
I've been around homebuilts and homebuilders since 1973, and have
learned much from the mistakes of others. The old guys will tell you
that you never design both an airplane and a powerplant at the same
time, and that you never design an airplane without training or
extensive research unless you are simply copying something else to a
great extent. I've met or read about fellows with odd ideas about some
"new" airframe who have either bankrupted themselves trying to make it
work, or nearly killed themselves trying to fly it. The majority of
these people weren't even pilots yet, just guys full of preconceived
notions. They spent an enormously frustrating amount of time and money
to no good purpose.
Auto engine adaptations are very time-consuming, and while
there are a few that run well enough, many of their builders wish they
had just bolted a Lyc to the firewall in the first place. Would have
been cheaper and they could have gone flying. I was also into boats for
some years, and knew a guy who did the auto transmission thing; didn't
last long at all. Those gears just won't take the high power levels for
very long. Cars don't cruise at 75% power, and that's all there is to
it. Detroit doesn't design stuff any stronger than it has to.

The key is you want someone else to do the pioneering work for you.
Several autoderivative engine conversions have flown and proven to be
essentially sound. I would use one of them or at least study them
intently.

I felt at the time Blanton had essentially the right idea but should
have made his drive a two piece casting, making his own patterns and
having them poured at a nearby foundry and using automotive machine
tools to finish machine them quickly. Today I suspect a enclosed HyVo
drive or even gears-probably from an Allison truck trans-with a quill
shaft might be better. Only Blanton's pathological hatred for GM kept
him from real success in terms of volume-everyone else wants GM engines
because they are staplles of the hot rod industry.