512 S and 512 M
These were not designated with P as they were not built for the 3000cc Prototype category, but with S as 5000cc Sports cars, of which at least 25 had to be built. Porsche had made that investment in early 1969 with the new Porsche 917. Ferrari answered with the Ferrari 512 which was introduced for 1970, and later modified as 512 M.
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