A head on a B block

Does anyone know if there is a problem running an A head on a B block?
Thank you for your thoughts.
If I remember correctly you need to plug two water holes in the block. Drill them, tap them and put an allen screw in with sealer. They are too close to the edge of the gasket.

Due to the shape of the combustion chambers you can run a A6050B head (the "Police" head) without plugging the holes.

Charlie Stephens
 
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In our club we have both:
• A head on a B block
• B head on an A block

No problems either way.
 
This should help you understand the differences in cylinder blocks. It is not necessary to plug the water holes in the "B" block regardless of the head gasket you use. An "A" gasket seals the 2 water passages, and the "A" cylinder head seals the water passages if you use a "B" gasket. I have done this both ways without any issues.

 

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The problem is that after 90 years the area around those 4 small holes in B blocks can be enlarged from corrosion, so need plugging. Plugs must be flush with the block to support the gasket, not merely plugged to seal water. If using the A head, an A gasket must be used, the gasket must fit the head.
 
Take a look at the steam holes on each side of the stud hole (circled)in Bob's B picture. Two of them. These are steam holes not water holes. They must be plugged as mentioned.
Notice they are not there on the A block.
 
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