In the late 1960s, facing stiff competition in NASCAR from Chrysler, Ford developed a new 429-cubic-inch V-8 with all-new free-flowing cylinder heads, an aluminum high-rise intake manifold, a 735 CFM Holley carburetor, 11.0:1 compression, header-style exhaust manifolds, and a beefy four-bolt main block. It was conservatively rated at 375 horsepower.

When dropped into the Mustang, it formed the Boss 429, a pony car with an abundance of muscle. To handle the power, the stout “Toploader” four-speed manual transmission and a 3.91:1 Traction-Lok rear axle were mandatory options. Other features included an engine oil cooler, trunk-mounted battery, competition suspension with front and rear anti-roll bars, power front disc brakes, and fat F60 × 15 tires. Unfortunately, upon initial construction of the new Mustang, the new 429 engine simply would not fit. Eager to start the production process and alleviate in-house headaches, Ford entrusted the modification work to local ally Kar Kraft. By cutting and relocating the shock towers, as well as relocating the battery, the new engine barely fit under the hood. However, in keeping with their hot-rod credo, Kar Kraft were able to shoehorn the engine into the Mustang.

The Boss 429 was the priciest non-Shelby Mustang to date, at $4,087, and it was available in very limited numbers, with fewer than 500 produced for the 1970 model year. According to the Deluxe Marti Report, this Boss was originally delivered to certified dealer Mr. Ray Whitfield Incorporated of Taylor, Michigan. The Mustang was specified with various optional extras, including power front disc brakes, competition suspension, a front air spoiler, and the drag pack.

Today the car sports its factory colors, striking Calypso Coral over black, and presents in excellent condition throughout. In the late 2000s, the car was the recipient of a complete restoration by marque experts Kevin’s Klassics of Cannon Falls, Minnesota. In recent years the car was also reported to have been judged by marque expert Bob Perkins, where it won a Concours Trailed Gold award from the Mustang Club of America.

Offered with thorough documentation and in excellent condition, this Boss 429 is ready to be enjoyed for its prodigious power.