Lot's of interesting comments on the subject of alternate engines.  I was convinced I was going to use an automotive V-8 at one time, but the last straws were the difficulty (or impossibility) of getting insurance and the low (or impossibility) of resae value.  As someone said, the resale value would likely be the same as an aircraft without an engine.  And my analysis showed that the installed cost would be about the same (or more) then for an aircraft engine.  But the internals of any of these engines are robust and should able to tolerate high continuous power.  My conclusions - opinions of the disadvantages:

 

V-8 with reduction gear:

Heavy - about 150 pound penalty

Complex installation and systems

Slight fuel consumption penalty

 

V-8 engine direct drive turbocharged:

Heavy - about 75 pound penalty

Complex installation and systems

 

Rotary engine:

Very complex installation and systems

Heavy - up to 50 pound penalty

Potentially fragile apex seals

Hgh cooling drag

Noisy

Significant fuel consumption penalty increases the weight penalty

 

Turbine engine:

High initial cost

High fuel consumption negates any weight savings

 

Misc. opinions:  The liquid-cooled V-8 dates back to about 1918 when Chevrolet built the first mass-produced one, so it's technology is even older than the air-cooled engine's "30's technology" that someone mentioned.

 

Gary Casey