Well over the course of a few years I've picked up a few 12G940 heads and currently have x2 in my garage that are visually different, the dirty red head with the raised top sections I'm clear on, these were on the mainstream Coopers, Metros, even going back to Maestro's, however what is the 'black' flat topped head? I was told each were from a mini & unleaded. they both have the 29 exhaust & 33 inlet valves and both 12G 940 with the addition of a logo rather like a M in a diamond and number stamping 578 on the flat top.
As always Mucho Gracias!!!
