Hi, I am trying to find out when ford changed stud sizes on the 300 I-6. My 77 came with self locking nuts. I need a valve job and I picked up another head which has smaller non-locking nuts and jam nuts. I can't make out the code on the head and am trying to figure out when they changed so I know the year of the head. They both have adjustable rockers and hopefully will interchange. Thanks in advance.
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.