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Re: 1275 Cooper S - Cylinder head

Posted: Sat Sep 12, 2020 10:50 am
by richardACS
Thank you gents, alot of experience being expressed here - will absorb and decide with what becomes available.

When one considers the amount of heads prepared by the tuners back in the day - where have they all gone?!

Re: 1275 Cooper S - Cylinder head

Posted: Sat Sep 12, 2020 1:38 pm
by Supersonic
In my opinion the 940 cylinder head is better by a country mile in that they are much more reliable than the early S head. One early 940 cylinder head you never see often is the Midland Motor Cylinder (RMC head). Most you see are the Wellingborough Foundry castings with the “W” in a diamond cast into the surface, whereas Midland Motor Cylinder castings had “WMC” or “RMC” along with the date, the year having a code letter. If you look closely at both cylinder heads sitting on my bench you can see they are slightly different castings noticeable near the thermostat area and above the plug holes.

Alan
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Re: 1275 Cooper S - Cylinder head

Posted: Sat Sep 12, 2020 8:51 pm
by Minisprinter
Why not just buy a MG Metro head it will out flow any S type head and be dead reliable to boot.

MS

Re: 1275 Cooper S - Cylinder head

Posted: Mon Sep 14, 2020 7:28 am
by mk1
I dropped off an absolutely perfect 163 off at Southam this weekend. It's going into my 1275 S build.

They do come up but you need to buy when you find a good one. No point trying to hold out for a bargain.

Re: 1275 Cooper S - Cylinder head

Posted: Mon Sep 14, 2020 7:32 am
by mk1
Everyone thinks the 940 is a better head & BMC were well aware of the shortcomings very early on.
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Re: 1275 Cooper S - Cylinder head

Posted: Mon Sep 14, 2020 8:44 am
by mk1
A couple of things to note about 163's.

In my experience, ones that have survived for 60 or so years without cracking, generally don't crack unless they are seriously abused.

Valve seats aren't necessary, but use of Lead additive or substitute is certainly worthwhile.

Repairs are rarely successful on these heads. They do work occasionally, but are generally not a long term fix.

An 1805 is certainly, undoubtedly, DEFINITELY a MUCH better option as a cylinder head, but having "the correct" cylinder head on your car is always nice.

Re: 1275 Cooper S - Cylinder head

Posted: Mon Sep 14, 2020 10:47 am
by richardACS
Mark

Thank you for your comments on the heads.

On another point; does much 'Downton' correspondence exist?

Richard

Re: 1275 Cooper S - Cylinder head

Posted: Mon Sep 14, 2020 1:18 pm
by mk1
Any that does is in private hands. I have maybe 20 or so letters altogether, aquired over the last 30 years or so. I know of a few people who have a lot of paperwork relating to specific purchases, but generally speaking, I imagine most was binned shortly after being read.