How many different casting numbers are there for aluminum BBC heads?

[AnthonyS]

Hi sYc Team, quick question as above.

I am aware of the below casting numbers but are there any other casting numbers for factory GM BBC square port Winters' cast BBC HiPo heads known? From back in the day I mean, I know there were some GM Performance numbers too later, also with the later part number config like 123...

I'm wondering on ones cast in the 60's - or if any were recast later with old casting numbers / old dates... I think when the blocks were cast later they were of a slightly improved design and were dated currently... did that happen with any aluminum BB heads too?

Numbers I know of for 1960s BBC aluminum heads:

3919842 / 842

3946074 / 074

and the non assembly line - production OTC 14011077 / 077

Wondering if there's other Winters produced casting numbers out there, thanks in advance all.
Anthony

[L78racer]

'67 L88 aluminum head cast #3904392

[AnthonyS]

Originally Posted by L78racer

'67 L88 aluminum head cast #3904392

Right! thank you.

Any other numbers anyone?

[Igosplut]

I once had an 842 head that was a later GM issue (late 70s, early 80s I believe). It had a different texture to the cast (much different), and I could never find a mate to it

[John Brown]

Have seen several of the 074 castings that had the better flowing 077 shaped exhaust ports. Must have been something that happened during changeover time.

[L78racer]

Originally Posted by Igosplut

I once had an 842 head that was a later GM issue (late 70s, early 80s I believe). It had a different texture to the cast (much different), and I could never find a mate to it

I have a pair of those. Texture is different. Several other things different on them but the basic head is the same.

[1971ls6]

The 074 casting with the 077 exhaust ports are very sought after. The issue is the castings have porosity issues and crumble, leak at the studs that go into the intake runners.

The 077 snowflake is different, it is more like a medallion and is easily spotted

[AnthonyS]

Thanks for the discussion everyone, I'm really not sure what I have here then.

I've got a pair of match dated 05-27-68 square port aluminum heads that I can't find any info on, even https://www.mortec.com/bbc.htm doesn't list the casting number.

(did they (GM) even make not-square port aluminum BBC heads?)

I assume they're GM as they have the snowflake...

But mine have a leading 0 casting number: 0313436 which is on a pronounced pad and each head has no less than five Winters snowflakes cast into it / them, one small one inside and a larger one over each exhaust port...

They recently came off a running Tri-Power Corvette and I was told there's about 5000 miles on them - they've likely been rebuilt before as they're stamped "L" and "R" & "OK" by the date. They have press in plugs.

Are these experimental pieces?

Thanks again everyone!
Anthony

[Flying Undertaker]

Anthony: The heads that you have are prototype (pre-production) heads. Any part numbers that start with a zero (0) or a zero dash (0-) are prototypes. I have a (0-xxxxxx) aluminum intake manifold with a winters snowflake emblem, as I am near the winter's foundry plant in Canton, OH. Don.

[L78racer]

Curious as whether they are open or closed chamber. Any pics of the bottom side?