Stage I Head Casting Numbers...

I have always understood that Stage one heads were mostly off the line heads with larger valves installed. I also have heard that there may have been a few special heads cast and referred to as Stage II heads. I pulled some numbers claimed to be casting numbers for Stage II heads from this Car Craft article: http://www.teambuick.com/reference/l...ormance-cc.php

and added them to our casting number chart: http://www.teambuick.com/reference/c..._big_block.php

While these four numbers are said to be casting numbers, I am wondering if they are actually part numbers for the Stage I or if they were actually a special casting for the Stage II, and if so, more of the story.

1970 1240150
1971 1240146
1972 1238530
1973-74 1242002

i don't see anything in the article that references the Stage 2 parts? i did a Ctrl+F for both "Stage II" and "Stage 2" and i didn't find anything that way either.



I also have heard that there may have been a few special heads cast and referred to as Stage II heads.


Stage 2 heads are designed so that they eliminate the exh port dogleg. there's a lot of material that has to come off of the exh side of the head in order to make this happen so *all* Stage 2 and up heads are header only. you can't attach an exh manifold if you want too.

i'm not sure if you could mill a standard head to get to a S2 type architecture, i'm thinking water jackets would probably be an issue.

Stage 2 cars were designed from the factory to use the Edelbrock B4B intake, TA has their own intakes.


http://www.buickperformanceclub.com/Stage2.htm


this article has pics of a Stage 2 head in the raw ( notice the massive, round exhaust ports ) and pricing / casting numbers. TA heads don't have perfectly round ports.

http://www.buickperformanceclub.com/455hdcompare.htm


there were only a couple of test mules built with these heads and about +150 head sets made by the factory. so pretty much everything Stg2 from back in the day is dealer or customer installed.

not much point in them beyond historical curiosity either. the original cast iron Stage 2 head is where TA got the design for their *aluminum* Stage 2 pieces. so, performance wise, you're much better off buying a new alum head from TA.


in TA terminology, "Street Eliminator" will fit an OEM cast intake while "Track Eliminator" requires a special intake.

Stage 1 will fit exh manifolds ( WHY? ), while Stage 2 and up require tube headers.

http://taperformance.com/products.asp?cat=421

oh yeah, there appears to have only ever been one Stage 2 casting number, 1235714.

they appear to have been for retail sale from late 1970 to early 1972.