I want 120hp from my EA 81 for an airplane, total weight muse be <200lbs.  I don't want the complexity of a turbo.

So, should I use a use a supercharger [which one?]; bore [re-sleeve] & stroke it for low rpm direct drive, or modify for high rpm reduction drive?

 

http://www.ramengines.com/

that website makes my pants fit funny

RAM 115A is a EA81.Its looks like they upped the compression ALOT(requires 93 octane gas, verses a standard ea81 that is quite happy on camp fuel),Then it is fuel injected.I don't think they bored or stroked the engine though.

 

So try 11:1+ compression,a cam that makes power around 5K rpm,then adapt a EJ18 MPFI and computer to work on it.

Look Here:

 

Information: ~► http://jodel.com/index.asp?p=subaru2&engines

 

Other EA81 for Aviation Vendor: ~► http://www.foxcon.com/Subaru-EA81.html

 

Foxcon develop a Different setup than RAM engines.

 

Kind Regards.