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MATCHING NUMBERS DEFINED
Be sure to notice that some parts have both a casting and a stamped date code. These can be several days apart. The stamped date code is when the part was assembled and should be the one considered. Engine Block The date code on a SBC is typically on the bellhousing flange behind the distributor. On early big blocks, it was on the passenger side near the pan rail, but later (1970) moved up to the same location as the SBC. See Engine Block. Usually the date is given as a letter, a number and then a number, such as B 23 3 which is for February 23, 1963. With any engine still having ignition shielding on, you have a very hard time to see the date. A good flashlight and a wire brush to clean any dirt are a must, even with the shielding removed. Cylinder Heads The date code is located on top under the rocker arms. You must remove the valve covers to see them. Often lead deposits in old engines have filled the numbers and letters so they are hard to read. Often the rockers are in the way. Intake Manifold The small block usually has the date on the driver's side rear runner. The date is typically below the casting part number. The firing order (18436572) is usually cast on the front runner so do not confuse it with the part number. Some big block intakes have the date cast under the intake so that you must have the intake off the engine to see it. Exhaust Manifolds The casting numbers on the Ram horn manifolds are on the outside near the 1-3 or 6-8 cylinders. On the big block manifolds, it is found low near the outlet. The date codes on the Ram Horn manifolds are found on the opposite end. On the big block manifolds, the date code is found on the back side. Transmission The Borg Warner transmission has a date cast into the main body and tailshaft in the early T10s. Some later T10s ('70s) have it also. Usually it is found on the passenger side. The Muncie has a date cast on the tailshaft. Unfortunately, these casting dates are the ones that the castings were made, not the transmission. A stamped number usually contains an assembly date. Rear end housing The housing for the 1963 to 1979 differential has a casting date on the drivers side. Again, this is the case date code. The assembly date is stamped in the bottom of the case on the lip where the cover mates. Alternator The date code is stamped into the housing. Water Pump The water pump has a date code cast into the body in the front but the pulley must be removed to see it usually. Carburetor Most of the earlier carburetors were built by Carter and had an identifier tag attached to a cover bolt. This tag had the part number and date code. On Holley carbs, the List Number is stamped on the drivers side air horn in front along with either a 3 digit or 4 digit date code. The Rochester QuadraJet has a stamped number on the driver's side on a vertical pad.