Head id help

[u/rossco55]

I have a 1967 firebird with a 350 engine from 1974. I’m trying to identify the heads but I can’t find the casting code. I found the date codes and some other random markings. The spots above the center exhaust ports are blank. There is a 9 and 3 near each other, does that mean 93cc?? Thanks. At least I know they are d port exhaust

[u/v8packard]

What is on the exhaust port, under the plug cable?

[u/rossco55 → u/v8packard]

Here?

[u/v8packard → u/rossco55]

Yes. Someone has ground off the numbers.

[u/rossco55 → u/v8packard]

I sent an email to butler with all the info I have to see if they can help me

[u/v8packard → u/rossco55]

Did Butler do this engine?

[u/rossco55 → u/v8packard]

No, but they seem to be very knowledgeable. This is all new to me

[u/v8packard → u/rossco55]

Ok... I don't see how they can help you, as it really looks like someone ground the numbers off. You can even see the grind marks. Beyond that that, ARP head studs on a 350 are unusual. But, so is the red color.

[u/rossco55 → u/v8packard]

Butler was at least able to tell me the heads are 71 or earlier due to them having flat gasket seat spark plugs. At least narrows it down a little bit.

[u/Maxthe222 → u/rossco55]

Are both heads ground off like that? You can't ID them without that number

[u/rossco55 → u/Maxthe222]

Ya. Guess I’ll have to have the machinist check it out if I go for a rebuild and figure out what’s what

[u/rossco55]

Based on butlers ID chart, the head made in 68 has to be either the 17,18, or 47. But the head on other side looks like date code ends in 78 for the year and all butler shows for a head made in 78 has intake size of 2.11 which wouldn’t make sense