The original name for the Porsche 911 was Porsche 901.
Porsche presented the 901 as the successor to the 356 at the Frankfurt Motor Show in September 1963. The model was still called the 901 when it appeared at the Paris Auto Salon in October 1964, and Porsche built a small number of early cars under that designation before customer production began.
French manufacturer Peugeot objected because it claimed trademark rights to three-digit vehicle names with a zero in the middle, such as a system used across its model range. Porsche responded by replacing the central zero with a 1, creating the name 911. The change was practical rather than mechanical: the car itself evolved into the production sports car that became Porsche’s defining model.
The 901 name did not disappear entirely. Porsche enthusiasts and historians still use it for the earliest cars, and the number also survives in references to some early Porsche part and transmission designations. Other Porsche racing projects retained internal numbers such as 904 and 906 but were marketed under different names, including Carrera GTS and Carrera 6.