Joint - cylinder head:

BMC 1H1049 (1500)       |
BMC 12H18  (1600)       | (These three numbers are interchangeable)
BMC 12H433 (1600, 1622) |
BMC AEH548 (Twin Cam)

Felpro/Payen     21183C  MGA 1500, 1600, 1622, all MGB 4-cyl
Moss Motors USA	 296-400  1500, 1600, 1622 stock type
Moss Motors USA	 296-405  1500, 1600, 1622 Felpro/Payen
Moss Motors USA	 296-395  Twin Cam  Bi-metal (CU on bottom, AL on top)

Moss Motors USA	 296-405 MGB 1962-1980, Felpro/Payen
Moss Motors USA	 296-415 MGB 1962-1980, copper

  MG-205 - Cylinder Head Gasket Changed (e)15688 (csm)
  MG-206 - Cylinder Head Gasket Changed (e)20501 (csm)

For as long as the off-site link might last, there is (was) a YouTube video for:
MGB Head Gasket Debate - Payen, Felpro/Payen, Lucas

From my own long term experience, beginning in the late 1960's, the original (OEM) laminated head gasket, with copper one side,aluminum other side,and something like asbestos in between, tend to leak and piss out coolant on the right side between spark plugs #2 and #$3. They are also prone to blow-out in the center hot spot between exhaust valves #2 and #3. This is worse on larger bore engines with narrower space at this location. So I consider the laminated metal gaskets as poison.

Until the early 90's,my suggested replacement head gasket was a silver fiber composite gasket (replacement for asbestos). This may have been the original Payen AK660. By appearance,it looks like it belongs on a Briggs and Stratton engine for lawn mower, go-kart or motor scooter. They do work quite well, never had one blow out or leak. But they can be sticky to separate next time the heed is removed, leaving residue that requires scraping off before installing the next gasket. There was an improvement with a shiny coating that may have been intended to be release agent, allowing it to come apart clean.

In similar time frame there was Felpro making a black fiber head gasket with metal edges aroundt the combustion chambers, but no rings around the water holes.

In the mid 90's I stumbled onto the black composite fiber gasket made by Payen, as it was supplied in some head gasket set. This was very good head gasket which I used for many years of competition driving, continuing to recommend it up to present day (2026). With some research, I discovered it was specified as original equipment for late model MGB 1800 engines, 1975-1980. Over time this gasket was improved some with crimped aluminum edging around the combustion chambers, and embedded raised red silicone rings around all of the water passage holes.

Payen was bought by Felpro, then merged in, with the gasket brand name changing to Felpro/Payen. Some time in the mid teens (if I recall correctly), manufacturing was changed to northern Europe (perhaps Turkey). With time the quality specification may have changed bit (cost reduction) with reduction of red silicone around some of the internal water passage holes. But as far as I know, this is still a very good head gasket.

About the same time there was advent of the "Lucas" brand head gasket, likely an offering of British Motor Heritage. Visibly it looks very much like the Felpro/Payen gasket with all of the red silicone, but is slightly thicker (heavier), being advertised as "Heavy Duty". Indeed it may be a very good and better sealing gasket, but it will lower the compression ratio slightly. The Felpro/Payen gasket measuring 0.050" new,( 0.020" thick when compressed), and the Lucas gasket being 0.030" thick when new. That is about 1-cc change of chamber volume. This might change compression ratio from 8.8/1 to 8.6/1, for example. Thus is likely not significant, unless you were building a race engine, in which case you measure everything anyway.

With Felpro stand-alone and Payen stand-alone both long gone, and Felpro/Payen being NLA in many cases, my current go-to would be the Lucas brand Heavy Duty head gasket (if you can find one). My latest procurement from Scarborough Faire in January 2026 was looking at two or three different parts under the same part number, none of them being Felpro/Payen or Lucas brand. Requesting a black fiber gasket, what I received was two of COBALT gasket, one now installed in my 1800-3-main engine, working well since mid April, about 5000 miles, and one for spare.