Cooper 'S' head

I have discovered that my '61 Midget has a 12A 185 casting cylinder head on
the 950cc block. Vizard refers to this head being among the better
performers along with the 12G 940 commonly found on the 1275cc engines.

Can anybody offer any more information regarding this Cooper 'S' head that
has the same size valves as a 1275cc head? I assume it is relatively rare
and I'm wondering if it is considered more valuable or desirable in a some
way. I haven't been able to find any reference to it in the Horler book, so
I'm guessing it never cam stock on a Spridget.

Thanks,

Gerard



G G              Gerard Chateauvieux
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  R R        pixelsmith@gerardsgarage.com
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    R G          Pixelsmith  on  Duty
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