What is a K-Code Ford Mustang?

If you’re a Ford Mustang enthusiast, you have probably heard other collectors talk about the K-Code Mustang. What was this coveted K-Code Mustang all about, and what made it so different from other models of its time?

The K-Code Mustang was a special-edition Mustang made between 1965 and 1967 that came from the factory with a special 289 high-performance cubic-inch engine beneath its hood. In its day, it was quite a beast on the road.

1965 Ford Mustang Fastback at Arnage neoclassic Cars

All About the K-Code Ford Mustang Package

Why was it called “K-Code?” The “K” stood for the engine code on the VIN number of these Mustangs. The K-Code engine was first introduced by Ford in 1963 and was featured in cars such as the Fairlane and the Comet.

Each K-Code Mustang had a special badge on their front fenders that read “HIGH PERFORMANCE 289”. No doubt about it, the K-Code Mustang was all performance. In fact, K-Code Mustangs were not available with air conditioning or power steering. And you couldn’t buy one with an automatic transmission until the 1966 model year. Prior to that, the K-Code Mustangs had only four speeds.

People often ask how the K-Code engine was different from the other 289 engines that fell under the D, C and A codes produced from 1965 to 1967 Mustangs. For starters, this engine featured upgraded pistons, cylinder heads, carburetor, lifter heads, and connecting rods. In addition, one look under the hood and you’d notice the chrome air cleaner and valve covers. There was also lettering on top of the air cleaner that read “289 High Performance.”

1965 engine 289 Hi-Po

Power Made the Difference in the Ford Mustang K-Code

With an estimated 271-hp engine on board, it was easy to tell this car from other 289 powered Mustangs of the day.

The differences didn’t stop there. In fact, the entire driveline of these cars was designed for performance. We’re talking about a high-performance clutch, drive shaft, rear differential, and suspension. It’s no wonder Shelby put the engine in his racing performance GT350 Mustangs. In fact, the first Shelby Mustang, the Shelby GT350R featured a modified K-Code engine.


These days, collectors of the Ford Mustang look back fondly on the K-Code. As such, these are highly sought-after Ford Mustang models. Unfortunately, only a limited number of these engines were produced between 1963 to 1967, and there were even fewer K-code Mustangs (only about 13,214 were made). If you own one, you own a valued piece of Mustang history and have a prized classic car commodity on your hands. If you want one, join the club.

If your are interested to buy a Ford Mustang K Code, please visit our inventory on Arnage Neoclassic Cars.