Author Topic: 3991492 head casting mark  (Read 1885 times)

billgodwin

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3991492 head casting mark
« on: May 15, 2021, 09:12:27 PM »
I have a set of heads on my car with the casting number 3991492. They also have an "x" cast into the space between the end intake and exhaust spring pockets in line with the head bolt hole. I've been told that the "x" is foundry mark. Can anyone confirm that or have info on this version of the 492 casting?

TIA

bcmiller

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Re: 3991492 head casting mark
« Reply #1 on: May 15, 2021, 09:37:27 PM »
I don't think they are anything special.  On SOME cast parts they used an X on early test type castings, but then on some heads like the 487X it does mean something.  I used to always look for the 487X castings, bought several sets and so far haven't used them.
Bryon / 1968 Camaro SS 396 coupe - now old school 468 big block
1967 Camaro RS/SS 396 coupe L35/M40 - 4 generation family project
Looking for 68 Camaro with body # NOR 181016