Development of a 4 stroke spark ignition opposed piston engine

Abstract

Abstract The purpose of this project was to develop a low-cost OP engine, 4-stroke, gasoline by joining two single-cylinder reciprocating internal combustion engines with side valves on the block, removing the heads. The chosed engine was Model EY15 of Robin America. Joining these two engine blocks together made possible to build an opposed-piston engine (OPE) with two crankshafts. In this new engine, the combustion chamber is confined to the space inside the cylinder between the piston heads and the chamber between the valves. The pistons move in the cylinder axis in opposite directions, a feature typical of opposed-piston engines. After building the engine, parameters characteristic of the OPE, such as: rotational speed, torque, fuel consumption and emissions, were measured on an Eddy currents dynamometer. With the collected data, power, specific consumption and overall efficiency were calculated, allowing to conclude that the motor with the opposed-piston configuration is less expensive and is more powerful. The development of the opposed-piston engine in this project has shown that it is feasible to build one engine from a different one already in use, reducing the manufacturing and development costs. In addition, higher power can be obtained with better specific fuel consumption and less vibration.