An Opposing Piston Opposing Cylinder ("OPOC") internal combustion engine combined with an externally mounted pre-ignition assembly with an internal swirl chamber to improve cold start and continuing operation. The pre-ignition assembly contains both a fuel injector and an ignition device that are in communication with the swirl chamber. The inlet/outlet passage opening that extends between the combustion chamber of the engine and the swirl chamber allows fresh combustion air to be forced from the cylinder of the engine into the swirl chamber during the compression stroke and allows the subsequently ignited plasma gases from the swirl chamber to enter into the combustion chamber as to the pistons reach their TDC positions.
