Info on these heads

Can anyone tell me about these heads?

 

Factory valve unshrouding in chamber

 

Sweet! So I scored a set of stage 1 heads? Is the service head a 70? Here is a picture of the valves and combustion chambers from both part numbered heads.

 

That casting number shows correct for 1970 and 1971. See http://gasalley.thetumbleweeds.net/tech_archive/buick/heads.htm

Devon

 

I could be mistaken but I seem to recall reading that big valve heads did not have the unshrouding and stage 1 heads did

 

That's what I remember, too.

Nice score, lt1b4c. Hopefully they check out fine for you!

Devon

 

They were free. The same guy called again today and said he found another set in his shop that I can have.

The heads came with a complete shortblock engine and intake manifold also.

 

Can I have a set? Since they are free I thought maybe?

 

Lol I need to verify these other heads first

 

There is a difference between big valve heads and big valve unshrouded heads. The big valve shrouded heads can be unshrouded by a competent machine shop.

 

It appears the heads I have are unshrouded. Did you see the pictures?

 

I like to start with a small valve head and machine them properly,but if those a free,and they are good,can’t complain about that.

 

inline - after 72stage1 of course

 

If they are 70 heads or even 71 heads, it looks to be they have aluminum rockers.
I thought they went to stamped steel ones?

 

My other 70' has aluminum rockers.

 

Huh..
Maby they changed to steel mid year or they came out in 71? I swear ever stock 70 head iv'e scene has the steel ones.

I just looked at my Max per Buick Engine book and it mentioned after 69 they went to 1.55 steel rockers.
Wondering if your heads were worked on or put on a 430 block and kept the 69 oiling? I am no expert though.

 

Wrong info in that book,....aluminum rockers didn't come into production till very late 71 and the full production in 72,..of you see a 1786 or 7661 head with steel rockers they were replaced

 

Hugger, now i'm confused..
The OP's pics seem have aluminum ones but was told they are 70 heads?

 

Yep, '70-'71 heads but they look like service replacements. That means that somewhere along the way, the first generation 455 aluminum rocker arms may have made their way onto these replacement heads.

First gen 455 aluminum rockers are not to be confused with '67-'69 aluminum 400-430 rockers, completely different design and oiling strategy. The first gen 455 aluminum rocker arms oiled through the pushrod, and all later 455 rockers did the same, but with stamped steel rocker arms.

Devon