another mystery engine number

I'm working on a 76' B and noticed the engine number is not for a "B", and I wanted to be able to tell the owner what he had, but I've ben unable to come up with anything. The number is BMH-1109-376E it seems I've seem a number like this before, probobly on a post here, but can't find that thread. Anyone have any ideas what this moter is?
The orig maifold and carb were switched over, but there is no water outlet in the back of the head, so there is an extension tee from the temp sending unit for the water choke. First time I've seen that.

Factory rebuild, otherwise known as Gold Seal or Silver Seal.

I found a web page that lists blocks with BMH

http://www.mgcars.org.uk/mgccz/technic/codeseng.pdf

Sorry typo the number is BHM-1109-376E
I was thinking a factory exchange motor originally, but then it should have a prefix of 8G, or 84G.
BHM XXXX XXX does sound like a BMC kind of number, but I don't see any reference anywhere.

The Gold Seal in my 75 in the UK had a number starting BHM.

I think it is a safe bet it is a factory replacement engine of one sort or another.

The "Practical Classics" book on MGB restorations had a chapter on factory replacement and rebuilt engines, along with various engine codes per country.

I think I have that book somewhere, I'll have to look.

According to Clausager, the Gold Seals started with either 48G or BHM. Practical Classics didn't list the code.

My version of Practical Classics did list the codes in a small table in the back, where it had about 2-3 pages on factory rebuilt engine options. Maybe they deleted this in the reprints?

My Practical Classics book doesn't have it, and my Clausinger book is loaned out right now. I'll look in it when I get it back.