The Ford Mustang K-Code was the epitome of pony car performance before the arrival of the Shelbys and Bosses. In an episode of Jay Leno’s Garage, Mustang enthusiast Scott McMullen discusses the significance of the K-Code and showcases a beautifully restored first-year example to Jay Leno.
Initially introduced alongside the Mustang in 1964, the K-Code was available for the coupe, convertible, and later, the fastback body styles. Often referred to as “1964 1/2” models, the first-year Mustangs, including the convertible featured in the video, carried this distinction due to their registration as 1965 models.
Opting for the K-Code meant receiving a more spirited variant of the optional 289-cubic-inch V-8 engine. This powerhouse featured a 10.5:1 compression ratio, a solid-lifter camshaft, a four-barrel carburetor, heavy-duty valve springs, and a high-flow exhaust manifold. These enhancements boosted the output to 271 hp, which was delivered to the rear wheels through a 4-speed manual transmission with the same ratios found in the later Mustang Shelby GT350.