I did my best to find the "How To" decode these marks. I have not figured it out. The best reference that I found:
http://mustangtek.com/FordDecodePlus.html
Does anyone have the key?






.150 Stroked Y-Block:327.25 ci @ >1hp per ci
 

Brent; the numbers 6090 were used as the core of a part number for heads..  You can link from this site down to John Mummert's site & go to cylinder head casting letters or numbers & also block numbers / letters too. It will give the year & application for nearly all heads & blocks manufactured in the USA... Some others marking may have to do with specific foundrys & date cast etc. I'm not really up on that information...   


Paul

The bottoms of  both of these heads indicate ECK B on the left, on the right one has A5 and the other has an X with a 5 barely visible. The head that has the X is marked as ECK-C on the face and the other is marked ECK-B. John's head chart shows the ECK-B to be @ 8.1 CR and the ECK-C to be @ 8.5 CR and he chart lists a "y" for the CC on the ECK-C and nothing for the ECK-B.











.150 Stroked Y-Block:327.25 ci @ >1hp per ci
 

Let me try ...

CASTING ID NOS. can be confusing but once the system(s) is understood, it begins to make sense.

During this period (50's roughly) FORD identified it's engines by a three character code, use EBU (1954 239 CI) for example.

These SERIES CODES (I am guessing on this term here) is also used as an ENGINEERING PART NUMBER PREFIX) to ID cast parts released for assembly/service.

So what you see is a three character prefix (again using EBU for reference), the ENGINEERING PN Basic PN (which will usually differ from SERVICE BASIC PART NUMBERS - example 6090 is the ENGINEERING BASIC PN and 6049 is the SERVICE BASIC PN for a bare cylinder head. Most ENGINEERING PN's can be converted to SERVICE PN's using FORD TEXT. The BASIC PN is not always shown on the actual part. The PN SUFFIX LETTER(s) gives more information.

The F surrounded by a C identifies the CASTING PLANT, in this instance CLEVELAND. There should also be somewhere the CASTING DATE CODE. The clockwork ID you see refers to what shift in the plant actually cast the part and gives more concise info than the CASTING DATE ID.

The other character(s) (X for instance) is a reference used in the foundry. It may or may not have a bearing on the casting as released for assembly/service.

The TECH SITE you showed refers to ID data mainly for the sixties/seventies era.

It is really not that confusing but now you see what a NUMBERS CORRECT restoration goes through.

Anything else, just ask.

NOTE:  I made a few corrections to hopefully clarify. Did this help or not? If not, I will leave it alone.

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