The Bourke engine was developed as a super-efficient, high power per weight engine for automobiles. Although it looks like a conventional opposed twin, the pistons actually move in the same direction left and right rather than in the usual “boxer” fashion of opposed movement. A Scotch Yoke movement in the middle transfers their horizontal movement into circular movement to turn the crankshaft. Despite his skill in making model airplane engines, Ralph Cooney was not successful in getting this engine to actually run at this small size, although prototypes at full size have been run.
