I see that Edelbrock is no longer listing replacement aluminum heads for Oldsmobile, and it appears that Summit has no Olds heads left in stock (typical for Olds parts).

I’ve looked at these Edelbrock heads in the past and they are listed as fitting all 1964 to 1977 Olds V8’s with the 350 & 403 requiring an aftermarket Edelbrock intake manifold.

I took my cast iron heads to a machine shop to have them redone (again) and they cut into the water jacket when removing a seat, so they obtained another set of cast iron heads.

How can I be sure that they are the proper heads, I’m pretty confident that they will work, but how can I determine the year of the heads? Can one tell by the numbers cast into the heads? I was told that they had a slightly different combustion chamber volume.

Old set – (397742) cast on surface under valve cover (742 cast on the head gasket side)

New Heads – (408 147) Cast over top of two center exhaust runners (147 cast on the head gasket side).

Any ideas or input?

Thanks,
Berts 442

 

I am not ery familiar with the casting numbers, but an internet search showed the 397742 was a 1968-1969 350 head, which would be a 5 head. I could not find the 408147 number but 409147 shows to be '71-'72 heads. These would be essentially the same as all SBO heads from 68-72 were very similar.

Olds heads have an easy identifier on the end of the head above the #1 / #8 spark plug area. Small blocks use a number and big blocks use a letter.
This link shows the various small block and big block head ID info:
http://www.442.com/oldsfaq/ofhed.htm

This is a SBO 7A (1972) head:


This is a BBO E (1970) head: