I have an engine ID tag from a 429 engine that we had pulled from a 1975 F150 XLT that otherwise looked stock. I am going to type up the ID as it is stamped on the tag.

429 72 11
12-23 K813 T

The above is how it is listed on the tag.
Can anyone make since of the above. I can already figure that 429 is the C.I. and 72 must be 1972. I can't make since of the rest.

Matt

 

~C.I.D. - 429
~Model Year - 1972
~Change Level - 11 (seems high)
~Yr. of engine production - 12 (Are you sure it isn't a 72 that would make a little more sense but also if the model year was 72 then i would think the production year would be in 71) (This is what th number would be in that location in a mustang so I'm thinking the same applies here)
~Where the 23 is is where the month of production would be but is usually a letter and not a number. In your case though with the 12-23 I'm thinking maybe it year the month and date. which is odd if so)
~Engine Code no. - I can't find a chart for K813-T, however in like a mustang an ID code of k826-k would stand for a cobra jet a super cobra would be an 829 and so on on the different variations.)

So the main stump is what exactly the 12-23 stands for.

 

Yeah the 72 is just as what is stamped. The tag is clean and free of rust. I tried decoding it myself but was also running into the same problems as the format apparently is not standard on this tag. I tried to layout the numbers and letters as the way they are stamped on the tag so that it would be easier to understand.

Matt

429 72 11
12-23 K813 T

 

429 4V from a 1973 Ford passenger car.

Letter prefixes and suffixes were used with engine codes after 1972.

Prior to 1973, the engine codes consisted of numbers only.

K 813 A; C; D; T = 429 4V / VIN engine code N / Engine assembled 12-23-1972.

Where did you find this code? It's not listed in any 1973/79 Ford or L/M car parts catalog.

1965/72 Ford car parts catalog: 826 = 429 CJ - F-4 // 829 = 429 S/CJ - F-4.

Info sources: Engine ID Charts / Text - Section 60 / 1965/72 & 1973/79 Ford Passenger Car Parts Catalogs // 1965/72 & 1973/79 L/M Car Parts Catalogs.

 

I found it on a mustang chart I'm not sure exactly where I found it I could try and look it up again. I'll do that once I get home.