A head on a B block

[Stick Shift]

I did a search and did not come up with anything. I was told you had to plug the two holes on a B block to run an A head. Any one have any input on this? Thanks Stick

[Tom Wesenberg]

This is true and I've posted a picture in the past. I threaded the block and used two set screws that take an Allen wrench. I turned the setscrews in just below the deck surface, then covered it with JB Weld. When the JB Weld thickened a bit I scraped it level with a razor blade.

[vulture]

Scott I have a B head you can have if you need it and can bring it to the swap. I know the B head has a better compression ratio.

[hardtimes]

Originally Posted by Stick Shift

I did a search and did not come up with anything. I was told you had to plug the two holes on a B block to run an A head. Any one have any input on this? Thanks Stick

Ooooh, you got a GOOD offer below that will preclude your having to do such plugs. Actually, there are FOUR of these quarter inch holes that should be plugged, if you intend to use the A gasket and aftermarket head.
The idea is to provide 'support' for the A gasket that is without these holes.

[Stick Shift]

Thanks guys. I was curious what would be the out come if the block did not get plugged? Would there be a chance of getting oil in the radiator?

[H. L. Chauvin]

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Hi Stick,

FWIW .......... just another different experience to share on plugging holes:

I ran a B engine with an A police head for years with no block holes plugged.

This B engine with an A Police head was also previously in my mechanic Uncle's boat for 15 years from 1932 until 1947 -- my uncle was born in 1905 & was a master mechanic -- he knew & taught me to never remove a head when the engine is hot -- so this A, Police high compression head never got warped, nor did the block because we never exceed 55 foot pounds.

Please call Mr. Ron Kelley, engine rebuilder in Texas for an ear full of his experiences & ask him how many heads & blocks he sees overstressed & warped at this center stud because of exceeding 55 foot pounds -- again, just different Model A experiences & input.

We installed this B engine with this police A head in my 1930 Coupe in 1958.

Also, the coolant in a Model A engine or a Model B engine is not at all pressurized.
Maybe just me; but why would this area leak if sealed with a good head gasket on a tight joint even with non leaking with a high compression head.

We always install the head gaskets with non-hardening Permatex No. 2 sealant on both sides .... more input.

However, if the B block or A head is warped here in the center, (where it usually warps at this very high stress point), it appears one may need to plug to plug the holes.

You asked for input, & this is just a different input -- everybody has input if you ask. LOL

[pat in Santa Cruz]

a B head breathes better than an A head too if you have that free offer in mind.. But if you're thinking of an A high compression head, then the A head modifications apply to those too.

[Bob Bidonde]

There is no need to plug any holes in the Model "B" block. Use a Model "A" head gasket and it will cover the extraneous coolant holes in the Model "B" block.

[Tom Wesenberg]

While what Bob says is often true, my friend's B engine with an A head had block coolant holes right at the edge of the gasket. This is living on the edge, especially with oversize head gaskets, which most of them are.

[Stick Shift]

Thanks for everyones information on the subject. Any thought or idea helps.

[Charlie Stephens]

Originally Posted by Stick Shift

Thanks guys. I was curious what would be the out come if the block did not get plugged? Would there be a chance of getting oil in the radiator?

Look at an A gasket on a B block. The B combustion chamber is more heart shaped than the Model A. You will see at least 2 (and as someone suggested maybe 4) holes that are extremely close to the edge of the gasket and not clamped by the A head. These holes will probably leak water into the combustion chamber. There will not be an oil leak into the radiator.

Charlie Stephens