Which head casting date is correct?

[Ramjett54]

I have an 02e 1968 z28 what would be the correct date range for cylinder heads?
I found some a28 castings, would they be within range?

[1968 Z28]

Don't know what is considered acceptable but here is mine for example.  Have an original 1968 07C Z28 that has an engine build date of 06-19 and the heads are dated E-9-8 and E-14-8.

[Petes L48]

Do you have the original block, or are you building a "date correct" engine?  You should be comparing the engine build date (stamped, and assuming it is not a fake/restamp) with the head casting dates.  Obviously the heads need to be cast earlier than when the engine was assembled.  This old thread and links found within may help, I think it has generally acceptable date spans:

http://www.camaros.org/forum/index.php?topic=6256.0

[x66 714]

I have an 02E 68 z/28 & one head is "A" late & the other is a "B" early. Can you contact me at jiaccino@cox.net? I have aquestion for you also. Thanks, Joe