I had the starter off so I figured that I would look up the the number on the block, and from what I can find on the web is its a 71 block out of a mustang, and that it's performance?

the code is
D1ZM-6015-AA
7-J0

so I decoded the D1ZM part but what is the rest of it? I know the bottom part is the casting date, but I cant find any information on a 3 digit code?

anyone have any insight? heres a pic of the code:

 

Looks like it's a Mexican block 302, they're supposed to be stronger. I'm not sure what the 6015-AA stands for but I'm guessing that it is what designates it as a Mexican block since I have one too except the first four digits are 75ZY.

 

mexican block with chinese frostplugs :-)

6015 means Engine block (so all ford engine blocks will have that)
AA is just a number that increases whenever they do a minor design change on the part. if they change something the part number would probably end in AB then

anyway the D1ZM at the front
usually you would see D1ZE, which is 1971 (c=1960, d=1970 ..., 1=1...). that's the model year, Z for what kinda car (most mustang parts carry 'Z', but that's not a 100%) and E for Engine part.

However yours is D1Z(!M!) which makes this block made in Mexico, which makes you a lucky man. They are sought after performance blocks

the number below
first digit is day, 2nd month, 3rd year
months are A-M (and 'I' is ommited). So J is Sep
7J0 is a datecode (7th of Sep). The year could be 1970 or 1980. however 1980 is quite far away from 1971 (D). So I guess that's a

1971 302 Mexican block made already on 7th of Sep 1970

that's a good reason to go celebrate and replace the chinese frost plugs with mexican ones *fg*

an easy way to identify seems to be the extra bumps in the front of the block:


you lucky man. they're supposed to be a great engine

 

thanks for the great info!

the funny part for this story is I picked the motor out of a 78 f-100 last year, and had the heads re-worked and their from a 69 truck...and from what I gather they had higher compression.

pretty interesting that I just so happen to pick this one.