Stock Eliminator Cylinder Heads

[SSDiv6]

Originally Posted by Ed Wright

After I built my flow bench (could not just buy a SuperFlow) back then) I was shocked at the variation of air flow between different castings, same casting numbers.

Yep. It is called "Core Shift". Caused by a deviation during the casting process due setting on the mold, mold alignment issues, mold temperatures and pressure differentials. One of the many reasons why the fast guys spend lots of money testing and going through many castings.

[Ralph A Powell]

Main issue is the pins and bushings on the cope and drag wearing overe the course of production. The foundries don’t pay close attention to this! Been in many foundries and they all have same problem from time to time. Lack of good QC.

Originally Posted by SSDiv6

Yep. It is called "Core Shift". Caused by a deviation during the casting process due setting on the mold, mold alignment issues, mold temperatures and pressure differentials. One of the many reasons why the fast guys spend lots of money testing and going through many castings.

[jimmyparker]

I'm pretty sure if you spend $6000 on a set of small block iron heads that "core shift" becomes a non-issue.

[Ralph A Powell]

Oh but you can have problems. It’s call the lawn sprinkler problems

[GTX JOHN]

Originally Posted by jimmyparker

I'm pretty sure if you spend $6000 on a set of small block iron heads that "core shift" becomes a non-issue.

If I thought that was true.....There would not be racks with a hundred plus sets of head castings in my shop. If core shift does not concern you = I have quite a few that you could get a really good deal on from me!


Just my .02
Your mileage may vary.

[Ed Wright]

Originally Posted by SSDiv6

Yep. It is called "Core Shift". Caused by a deviation during the casting process due setting on the mold, mold alignment issues, mold temperatures and pressure differentials. One of the many reasons why the fast guys spend lots of money testing and going through many castings.

I knew a local machine shop that had a back room full of castings. He let me take several for testing. My ‘56 was newly allowed the “520” castings. I discovered the 520X castings.
Held more CCs than legal. I had decked my block a lot, so needed to mill the intake side of my heads a lot so the manifold would fit. Got rid of some intake CCs.