Casting vs stamped block numbers confusion

[jeepthrills01]

Ok...so we all know since there was a human involved in stamped numbers theres a greater chance for error...casting numbers would have had a few sets of eyes on them (at least I hope so).

I finally got access to the stamped numbers on my 69 318...I had previously verified casting numbers dating to 1968 which makes sense as my car was a January build.and the vin is there too. The stamped numbers say something completely different.

P= 1979
M= Mound Rd
318...
R= regular

The 2331 fits late 1968
The 2263..boy they were busy.
So the first P...if not a year..what's it mean?

 

[69Bee]

I can't find the chart I used to decipher my 1960 318 poly, BUT I believe the P could dictate "Plymouth", it did in my case. You are correct with the rest. As far a the sequence number 2331 is 15 Dec 1968 and the 1263 is the 1262nd car built.

The other stamping (P39991P) is from a rebuilder. I hate when shops do this. I use a sharpie to ID the jobs.

 

[69Bee]

Letter Stampings Designating Year of Manufacture (R-17):

R: 1961
S: 1962
T: 1963
V: 1964
A: 1965
B: 1966
C: 1967
PM, PT or DW: 1968
E: 1969
F: 1970
G: 1971

 

[jeepthrills01]

I took the meaning as
1st digit= year
2nd digit=plant
3,4,5 = displacement
Anything beyond as special notes.(r=regular, p=premium etc)

But I'm guessing now the date is just in the julian 2331.
Dosent the 1263 refer to unit built..as in engine? That's what I assumed cause this is info added at the engine assembly plant.


And the other P on the right matches the build sheet sequence numbers

There is also a small upside down & backward B straight down from the R in 318R. Anybody know?

 

[Ernie ingling]

In the 70’s chry would refurbish warranty engines and put in new cars. So the new stamping is rebuild date.

 

[MCODECUDA]

The important number that you should be looking for is stamped above the oil pan rail on the passenger side of the block. This number will correspond with the vin number. Depending on the plant it could be the partial or complete viv.

 

[jeepthrills01]

.I had previously verified casting numbers dating to 1968 which makes sense as my car was a January build.and the vin is there too.