Quote from C6ZZKGTHipo 289 rod bearings are a C3OZ part number where the standard bearings are a C2OZ part number. The Hipo rod bearings are of a tougher material than the standard 289 rod bearing. It would be equivalent to a Clevite 77 bearing.
-Fred-
Parts houses show the Clevite number as CB 676 P and the A or C code as a CB 643 P. When trying to order the 676 pn gets superceeded by the 643. Not sure what is correct!