Engine: Application and ID

A letter code is used to denote size of the bore, main bearings and rod bearings. This code is located on a boss above the oil filter. This letter code is as follows:
Letter ``B'' - Cyl. bore .010 inch oversize.
Letter ``M'' - Main bearings .010 inch undersize.
Letter ``P'' - Rod bearings .010 inch undersize.
Letter ``C'' - Camshaft block bore .010 inch oversize.
Letters ``PM'' - Main and rod bearings .010 inch undersize.