More about Subaru engines

06 Nov 2003 More about Subaru engines

Update 20210918: I didn’t install the Eggenfellner Subaru engine, so any post that references that can be ignored or used as a cautionary tale about how to avoid wasting many years and $50k.

I was recently reminded:

> The standard Lycoming/Continental motor is
> designed to purr along all day at 65/75% power. 

Don’t you mean “shake and rattle”? 🙂

I’m not sure which is more important in an airplane engine, raw horsepower or torque. If it is torque, then this graph from NSI Aero shows that they don’t have much of a problem at lower RPM.

http://www.nsiaero.com/nsiaero2/4.0/4.1/4.1.4/4.1.4.6/Enginedyno.jpg

Looking at the Bombardier site, they claim their peak performance at 6000 RPM, just like the Subaru. I’m not really sure what they would do differently from an auto engine to have an engine that was designed for aviation, and their web site does not give many answers to that question.

I don’t see any advantage to a water cooled engine in reducing drag. Both engines will generate a lot of heat that needs to be removed from the cowling area into the airstream.

There are quite a few details on why the Subaru is a good aviation engine on the various suppliers web sites, and I found this somewhat dated link here to more info: http://www.geocities.com/subaru_builders/

The most frequent question type that I get from people that hear that I am planning on installing a Subaru are of the type “what if you lose a cylinder and you need replacement parts” or “you can’t overhaul a single cylinder, you have to replace the whole engine”. I have a suspicion that none of us on this list have had to replace any major components of our modern (post 1980) car engines before they reached their rated life span, have we? Compare that to your group of friends and their aviation engines. Some people just say “the devil you know…”