Sounds like you have a Fox .36X combat engine. They made numerous versions of the engine over the years for control line combat competition.
Fox combat .36X engine history:
http://www.clcombat.info/foxhistory.html
More about them here too
http://www.clstunt.com/htdocs/dc/dcb...opic_id=331805
and we discussed them some here too
http://www.rcuniverse.com/forum/glow...ox-engine.html