I'm trying to determine if the block in my 70 RS/Z28 is the original engine. The block casting number is 3970010. There is nothing on the block pad so I assume the block has been decked. All I have the is casting date code (see attached pictures). The casting code reads 0 D 14. If I'm correct, this decodes as 70, April 14th. What I'm confused about is most reference materials indicate the casting code format is Month Day Year. Which would mean the casting date is April 1st 74. Looking for clarification. Thanks...
There was some variation in how these casting marks were made between engine casting plants. It is also possible that as time passed, sometimes things were done differently. If this is a Norwood Camaro, Nowwood didn't stamp the partial VIN on the front engine pad. They stamped the VIN on the rough area of the block casting above the oil filter. Look there for your VIN.
All 70 z28 engines came from flint as they were the only plant that had the machinery to cut the cylinder heads to unshroud the chambers for 2.02 valves. They are unique as they have the oil gallery plug on the front of the block. Mine looks li,e this for a 05b built car.
