Pontiac 400 428 455 Engine Codes. ... 1949 Chevrolet Sport Coupe ... This is a quick block ID for junk yard hunting, etc. You must find the date code at the back LH ... Chevy Small Block - Engine Block Casting Numbers Notes (for below): "High Power" is the maximum rate HP this block was used for, "Low Power" is the lowest rated horsepower RPO engine the block was used in. "Main Caps" is the number of bolts holding the cap. A "two-bolt" main, or a four-bolt main.

The engine assembly stamp (aka, "engine code") identifies the engine assembly plant, assembly date, and engine application suffix code and was stamped by the engine plant. It is located on a machined pad on the engine block. For V8's the pad is a forward extension of the passenger-side engine block at the bottom of the forward end of the head. Chevrolet's 3rd and 4th generation small block engines are generally known by their RPO code. You can determine the RPO code if you have the Vehicle Identification Number (VIN) from the original vehicle. Locate the 8th digit of the VIN. Consult the tables below to identify your engine. Notes