1275 Cooper S - Cylinder head

General Chat with an emphasis on BMC Minis & Other iconic cars of the 1960's. Includes information on MK1 Action days.
richardACS
Posts: 151
Joined: Tue Jun 19, 2018 2:43 pm

Re: 1275 Cooper S - Cylinder head

Post 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?!

Supersonic
Posts: 1931
Joined: Fri Mar 20, 2015 5:25 pm
Location: Crossgar County Down Northern Ireland

Re: 1275 Cooper S - Cylinder head

Post 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
DSC01553.JPG
DSC01552.JPG
DSC01551.JPG
DSC01550.JPG
DSC01549.JPG
You do not have the required permissions to view the files attached to this post.

Minisprinter
Posts: 118
Joined: Sun May 27, 2018 7:32 am
Location: Essex (not the white stiletto bit)

Re: 1275 Cooper S - Cylinder head

Post 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

User avatar
mk1
Site Admin
Posts: 15395
Joined: Thu Jun 24, 2010 11:30 am
Location: York-ish
Contact:

Re: 1275 Cooper S - Cylinder head

Post 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.
Mark F
General dogsbody.

User avatar
mk1
Site Admin
Posts: 15395
Joined: Thu Jun 24, 2010 11:30 am
Location: York-ish
Contact:

Re: 1275 Cooper S - Cylinder head

Post by mk1 »

Everyone thinks the 940 is a better head & BMC were well aware of the shortcomings very early on.
dtn_163_letter.jpg
You do not have the required permissions to view the files attached to this post.
Mark F
General dogsbody.

User avatar
mk1
Site Admin
Posts: 15395
Joined: Thu Jun 24, 2010 11:30 am
Location: York-ish
Contact:

Re: 1275 Cooper S - Cylinder head

Post 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.
Mark F
General dogsbody.

richardACS
Posts: 151
Joined: Tue Jun 19, 2018 2:43 pm

Re: 1275 Cooper S - Cylinder head

Post by richardACS »

Mark

Thank you for your comments on the heads.

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

Richard

User avatar
mk1
Site Admin
Posts: 15395
Joined: Thu Jun 24, 2010 11:30 am
Location: York-ish
Contact:

Re: 1275 Cooper S - Cylinder head

Post 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.
Mark F
General dogsbody.

Post Reply