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Hemi Identification: Part II

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Tags: Tech, Hot Rod, Street

Here we will break down where to find identification numbers on early Hemi’s and what they mean.

Please note this is a guide for most automobile, truck, industrial, and marine applications. I have done my best to pull together the best data available as of this writing.

Block numbers can be found stamped into a flat portion of the block located just in front of the valley cover. Here are a few examples:

First a Dodge, then Desoto, and finally a Chrysler block all of which can be deciphered with the chart below.

Dodge block numbers
Desoto block numbers
Chrysler block numbers

Head casting numbers can be found by removing the valve cover. Note that “Triple Nickel” or “555” heads make reference to the only casting number that has three “5”s in the part number (non-sequential). These have been said to flow better than any other Chrysler heads.

Engine head casting numbers
Engine head casting numbers

Connecting Rod casting numbers can be found on cast on the “I beam” portion of the rod. The example below is a NOS 392 rod.

NOS 392 rod

Crankshaft part numbers can be found on the counterbalance portion near the center of the crank.

Crankshaft part number
Part Number Chart

Once you find your part numbers and want to begin deciphering them please refer to the chart linked here.

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