Paddy's ZB Manifold is now on, I think it feels much brisker!
To fit the 1.1/4" manifold it needed some spacers making up, but not a problem! Thanks Paddy!
David

If it's any help (and not too late) I'm sitting on a couple of unwanted Magnette ZB manifolds. They are a straight swap for the original model (the one with the square block in the middle) but a lot more free flowing.

If you are interested let me know by Email a35(at)sky(dot)com.

Paddy

Dave, If the gasket has blown the risk is the head is warped, so I would skim the head to make sure, the 'O'rings you have will go hard and break up, very quickly the originals certainly did and the repro stuff is rarely any better, , Rimmer do seals for Rover and Triumph which fit straight on and are worth every penny, they are like little top hats.
Part of the reason why the gasket might have blown is the compression ratio is probably 10/1 the 1500 head has a combustion camber capacity of about 38 cc , less if the head has been skimmed , it could be 35cc easily, so 11/1 CR is more than likely, where as the MGB is 43cc .

Trevor

I'm stuck with the 1500 head at the moment. I do have an original BMC copper one side, steel the other gasket. I was not familiar with the spring loaded stem seals. I have "conventional", rubber (or whatever) O ring type from NTG. I have given up on the idea of the double springs & will use singles again.
I will use highest octane fuel & take care with the timing.
As a project I will look out for another head, but feel that if I go down that route I will be seduced into bigger SU's free flow manifold ( which will be too big for the tiddly Stainless exhaust ......it never ends!
Thanks for the advice...even if I'm rather ignoring it!
D

David
Malcolm is right, the 1500 head will also give you a very high compression ratio as the combustion chambers are smaller on the 1500 head, any MGB head will do but you need the correct rocker shaft pedestals for the later heads as the oil feed is offset.

When you replace the head gasket make sure you use a good quality head gasket, with copper facing , ideally Payen or similar.

Trevor

David,

Are you planning to put the 1500 head back on? You'd do better with an early MGB head if you can find one. Original 1622 heads are very scarce.You'll get more benefit from the 1622 block with the bigger valves in a later head.Have a look at the MGA Guru website; there's a lot of relevant stuff about head interchangeability.

If your gasket has blown between the middle pots, the chances are that the metal there has eroded and you'll have to take quite a bit off to get back to level. You may as well do the work on a better head with all the latest oil seals etc.

Malcolm