The FZ93 stands for "Formula Zagato '93" and was created as a concept car in the Testarossa lineage. Ercole Spada designed it as a continuation of Zagato's series of custom Ferrari coachbuilt models. In 1994, the car was reworked, painted entirely in red, and renamed ES1 in honor of its designer.
Summarized from the sources cited below; every figure in the text was automatically verified against the sources.

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