Executive stylist John Najjar, who was a fan of the World War II P-51 Mustang fighter plane, is credited by Ford with suggesting the name.[10][11] Najjar co-designed the first prototype of the Ford Mustang known as the "Ford Mustang I" in 1961, working jointly with fellow Ford stylist Philip T. Clark.[12] The Mustang I made its formal debut at the United States Grand Prix in Watkins Glen, New York, on October 7, 1962, where test driver and contemporary Formula One race driver Dan Gurney lapped the track in a demonstration using the second "race" prototype.[13]
An alternative view was that Robert J. Eggert, Ford Division market research manager, first suggested the Mustang name. Eggert, a breeder of quarterhorses, received a birthday present from his wife of the book, The Mustangs by J. Frank Dobie in 1960. Later, the book's title gave him the idea of adding the "Mustang" name for Ford's new concept car. The designer preferred Cougar (early styling bucks can be seen wearing a Cougar grille emblem) or Torino (an advertising campaign using the Torino name was actually prepared), while Henry Ford II wanted T-bird II.[14] As the person responsible for Ford's research on potential names, Eggert added "Mustang" to the list to be tested by focus groups; "Mustang", by a wide margin, came out on top under the heading: "Suitability as Name for the Special Car".[15][16] The name could not be used in Germany,[14] however, because it was owned by Krupp, which had manufactured trucks between 1951 and 1964 with the name "Mustang". Ford refused to buy the name for about US$10,000 (equivalent to $94,356 in 2022)[17] from Krupp at the time. Kreidler, a manufacturer of mopeds, also used the name, so Mustangs were sold in Germany as "T-5s" until December 1978.