The FX is a bespoke commission built by Pininfarina at the request of the Sultan of Brunei. Mechanically based on the F512 M, it adopted its twelve-cylinder boxer engine, paired with a seven-speed sequential transmission sourced from the Williams Formula 1 team. Depending on the source, seven or nine examples were built, six of which went to the royal family. The fourth car was acquired by Dick Marconi from Williams after the Sultan canceled delivery; today it resides in the Marconi Automotive Museum in Tustin, California. The FX name resurfaced later during the development of the Enzo.
Summarized from the sources cited below; every figure in the text was automatically verified against the sources.
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