As far as I'm aware Cosworth did the head work on the 16 valve 190's other
than that I don't think they had a great deal of input, There may have been
a limited number of race cars produced that were made in a state suitable to
be heavily tuned, 500 would make sense as that was the Homogulation number
required for a car to be classed as "Production" Hence the Ford Sierra RS500
Cosworth of the same era.
Certainly not a road vehicle that I'm aware of in the UK.
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