Different numbers at the "4" position reflect code for which manufacturing plant making the 226 built the particular engine. 1947-48 Kaisers and Frazers could be equipped with engines from either Detroit Engine Division (the Continental Engines plant on Detroit's east side that Kaiser-Frazer manageed and later acquired from Continental ) or the Continental Engines complex in Muskegon, Michigan. The information was needed by Kaiser-Frazer Sales Corporation for charging back the engine plant that made an engine that required warranty repair in the field.