Chevy OE cranks, cyl. heads.

[Tim H]

I am interested in learning where Chevy SB Gen 1 and BB Mark IV OE V8 crankshafts and cylinder heads were manufactured ?
thanks in advance

[Greenlight]

Most were cast at the Saginaw (part of GM's "Central Foundry Division") and Tonawanda foundries. The machining for the Saginaw cast heads was performed at the Flint Engine Assembly plant. Tonawanda had it's own machining facility.

You can find additional information here.

http://www.camaros.org/pdf/cast_codes.pdf

https://media.gm.com/media/us/en/gm/.../defiance.html

[Adger Smith]

Very interesting information there about the "Banking" process GM did on the 3872783 intakes. Makes you go, humm..

[Greg Reimer 7376]

That's absolutely fascinating reading how they did all that. We've all seen parts with the same casting number,say, an #803 intake or #3917290 heads, or #462 heads, and as long as they conformed to the tech info in the classification guide, the rest of the numbers didn't mean much. This does a lot to update info on what the rest of the numbers mean.

[Adger Smith]

Greg
I have been doing engines since I was in High School back in the mid 60's. I have seen head cores that are all over the place with numbers.
I have seen cores that came from 2 different core box sections. Like down in the water passage there is a 487 cast in the bottom mold and then a 992 up on the top with the shift and mold and date codes. To me that just tells me that the foundry put two core boxes together to keep production up. You know they do anything to keep production going. Every one I have seen with a 487 in the water passage had a large volume intake runner. Like they used the bottom half of the core as a 487X and the top with another number on it.
I'm pretty sure there were some old guys back then that were savvy to anomalies like this and ran faster than those of us that had not figured it out.
OK, Billy and Dwight run with it..

[Ed Wright]

I was fortunate enough to find a local shop with a large inventory of cylinder head castings when I had my old C/SM car. Had to use production head castings, with very little porting allowed. Remember one inch below the seat?
I was able to locate five 461X castings. Of course picked the two my flow bench liked the best to start with. Seems like the "X" Intake ports were about 5cc larger?
The 5 #461X castings I found did also flow a little more on my home built bench than the regular 461 & 462 castings I had. A little more than those other castings normally varied. Even better after Lee Shepard laid his hands on them. I was more impressed with the X castings than Lee was. Think Lee knew more than me? LOL

[Billy Nees]

I have always been told that an X was put into the core box when it was worn out.
Now, that could make sense or maybe there were some Racer types loose in the foundry who had found some really good core boxes and made sure that special projects used these pieces.

[bubski]

This could be the smoking gun as to the great 283 intake travesty !! But the 'damage is already done ' !!! OMG the 283s are taking over the eliminator !!!

[Greenlight]

Some additional links that may not be as useful, but refer to casting marks such as "CFD" (Central Foundry Division) and engine markings "F" (Flint) and "T" Tonawanda being used to identify origin.


https://www.mortec.com/location.htm
https://www.mortec.com/locatpg2.htm

http://hotrod.gregwapling.com/chevrolet/mckinnon.html

https://news.pickuptrucks.com/2011/0...g-center-.html

[Ed Wright]

Originally Posted by bubski

This could be the smoking gun as to the great 283 intake travesty !! But the 'damage is already done ' !!! OMG the 283s are taking over the eliminator !!!

I had one pair, and saw one other 520X. My '56 was gone by then.
Never found any X castings for my LT1. LOL