These cars don’t exist. Not really. Technically, every first-year production Mustang is a 1965. But the first cars rolled out of Ford’s Dearborn plant on March 9, 1964, and Mustangs built before August 17 are considered 1964 ½ models by those in the know.
The early cars can be difficult to identify, but there’s a long list of tells, including their generator and the Eaton power-steering pump. Hardtops and convertibles only, they were powered by a 170-cubic-inch inline-six with 101 horsepower (the U-code engine), or two optional V-8s, a 164-hp 260 (F-code), or a 289 (D-code) rated 210 horsepower. The K-code Hi-Po 289 was added in June, and the rest of the engine lineup was revised in August.
[Editor’s Note: This story originally appeared as part of the 25 Greatest Mustangs cover story in the July/August issue of Hagerty Drivers Club magazine. You can find the other entries here.]