Reply to "Mysterious ‘China-wall’ gap"

Originally posted by LF - TP 2511:
Thanks for all of the suggestions.

We have pulled the intake and heads off of the engine due to a dyslexic and asleep at the wheel problem regarding the head gaskets. Turns out the Fel-Pro gasket number for a Windsor is 1031 and the number for a Cleveland is 1013. I’m afraid you all can guess what happened, just glad that I caught the problem when going over the build sheet.

I am returning to my engine builder tomorrow but fear he has already installed the heads this afternoon. I did tell him to delay installing the manifold pending further investigation on this issue.

Whether the ports are raised or the manifold was somehow incorrectly machined are both certainly questions worth answering. However, since everything bolts together just fine I am inclined to just find an acceptable manner to fill the large gap rather than try to diagnose exactly what is happening.

I have learned another owner had his engine builder fabricate spacers when faced with this problem.

Is anyone aware of a source for pre-made end valley spacers?