Mini Cooper/MG 1275cc Factory Competition Cylinder Head.

The 12G1805 was a precursor of the 12G940 developed initially by Daniel Richmond at Downton Engineering, close to his other interests, 'The Bull at Downton' and the Hampshire Avon, a premium fly fishing river

. Used by the factory competition department, for competition Coopers and MG Midgets, these heads were subject to chamber and port shaping for performance results. The personal marks of the factory fitters involved can be seen, also the identifying 12G1805 number.

These heads were cast differently to give more material for even further shaping of ports/chambers.

But enough history, today the head, 02F, is as you see here. All aspects of it are shown during the refurbishment.

The overall condition proved remarkably good. Head deck thickness substantial, water by-pass blanked off. Water passages clean of any build-up. Valves and guides excellent, stem seals to inlet valves. Double spring sets complete with inner spring centering bottom washers and good top caps.

Head stripped, chemically cleaned and checked for cracks and porosity. Exhaust valve seats recut and valves refaced then all valves hand lapped for best sealing/compression.

This ready to fit, 940 competition head, has NOT been modified for unleaded petrol.

For daily, off motorway motoring, these heads run very well on unleaded fuel. For competition/motorway work, use an additive such as Millers VSP Plus.

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Finished head repainted MGOC 'BMC Green Engine Paint'. Meticulous assembly followed.

This offers an unusual opportunity to upgrade your 1275 for more performance whilst retaining period originality.