Lists of casting numbers General Motors engine blocks can be found online at OutInTheShop.com, NastyZ28.com and GearHeadGeek.com. All three sites list GM engine block casting codes in numerical order with the corresponding engine information, year range of production, and when possible, a brief description or identifying characteristic of the engine.
All three sites also have a search tool that allows users to input a GM engine casting number to return a result. CastingNumbers.info helps cross reference casting numbers from other engine components back to a particular engine type and casting number. NastyZ28.com also provides information that helps decode the engine code casting numbers to provide more information about the GM engine.