EEC-III was introduced in 1980. It is a third generation system developed entirely from EEC-II. The only real differences between EEC-II and III are contained within the Electronic Control Assembly (ECA) and the DuraSpark ignition module. The EEC-III system uses a separate program module which plugs into the main ECA module. This change allows various programming calibrations for specific applications to be made to the program module, while allowing the main ECA module to be standardized. Additionally, EEC-III uses a DuraSpark III ignition module, which contains fewer electronic functions than the DuraSpark II module. The functions have been incorporated into the main ECA module. There is no interchangeability between the DuraSpark II and III models.