Abstract: A motor has an engine block with cylinders arranged to fire in a firing order. A recirculation system delivers combusted mixture from a cylinder which has just fired to at least partly mix with fuel for the next cylinder in the firing order. Injector bodies (401-405) are associated with each cylinder. Each injector body (401-405) has an internal chamber (424) in communication with a fuel inlet port (426) for delivering fuel into the internal chamber, a fuel outlet port (428) for delivering fuel under pressure from the chamber into the associated cylinder and a combusted mixture out-let port (442). The combusted mixture outlet port (442) of each injector body (401-405) is fluidly connected to the combusted mixture inlet port (438) of the next cylinder in the firing order. Alternatively, the recirculation system is arranged substantially internally within the cylinder head.