Engine Unit Number - Decoded and other Information


Number          Shop Manual Name    Description/Location(s)                              
44K2076        Engine Unit Number    Top Rear of Engine by Oil  Pressure sending unit, etched into block.


44K is the Engine Unit # prefix that identifies the engine type. For this example it means this engine was intended for a 6039,  6329, 6339, 6357, 6367, 6267 with air.

2076 denotes the numerical order in which this engine was built.

A decode card for Prefix codes is located on page 1-2 of the 1963 and 1964 shop manuals.    

Decode Info for 1963 390 Engines

Body Styles Engine Unit No. Prefix 

6039, 6229, 6257, 6267, 6239, 6329, 6339, 6357, 6367, 6389 without air cond

6039, 6229, 6257, 6267, 6239, 6329, 6339, 6357, 6367, 6389 with air cond 36K
6723, 6733, 6890 without air 37X
6723, 6733, 6890 with air 37K

Decode Info for 1964 429 Engines

Body Styles Engine Unit No. Prefix 

6039, 6329, 6339, 6357, 6367, 6267 without air

6039, 6329, 6339, 6357, 6367, 6267 with air cond. 44K
6229, 6257, 6239 without air 46X
6229, 6257, 6239 with air 46K
6723, 6733, 6890 without air 47X
6723, 6733, 6890 with air 47K


Example 1963 390 Casting # and Engine Unit Number
Example 1964 429 Casting # and Engine Unit Number

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