2003 Cobra Block Markings

[USMC53CHIEF]

I'm familiar with the yellow paint blob on all the iron block 4.6's, but I am curious if anyone knows anything about the other writing. This is a 2003 Cobra motor.

 

[rzimmerl]

Those look to be marks from a person that did a check part on that block from the block machining line.

 

[USMC53CHIEF]

Base doff the dates of all the other parts, looks like it went through 1/22/2003. One of the heads is a 12/2002 and the other is 01/2003