The BR114 are a fleet of rebuilt BR143 that were modified to raise their maximum speed from 120km/h to 140km/h. A test conversion to 160km/h was also made however the conversion to 140km/h was significantly cheaper than the conversion to 160km/h. Since major components of the locomotive did not need to be rebuilt and converted to run at the maximum speed all subsequent BR114 conversions were updated to 140km/h as the cost benefit was not worth the conversion to 160km/h.

A number of other minor improvements and modification were made to the fleet such as replacing the old pantographs with newer models. With this new fleet of rebuilt locomotives the BR114 was more aptly able to serve its role as a passenger locomotive and increase the efficiency of the routes they operated on.