205/70R15 is 26.3 inches diameter.
215/65R15 is 26.0 inches diameter
235/60R15 is 26.1 inches diameter.
F60-15 is 26.1 inches diameter.
255/55R15 is 26.04 inches diameter.
285/50R15 is 26.2 inches diameter.
Size My Tires/Compatible Vehicles
According to the link above 235/60R15 size tires are OEM for Camaro/Firebird, DeLorean, Jaguar XJS, and Lotus Esprit. Plus the F60-15 size tire was a very common tire on 1969 and later American muscle cars, such as Mustang. Nothing comes-up for 285/50R15 however.