During the mid-1960s, the non-competition agreement adopted by the Big Three nearly a decade earlier had fallen apart, with increasingly open factory-based support provided to supposedly independent racers. Ford, in particular, faced stiff competition from Chrysler in NASCAR competition. The Blue Oval camp required a new engine, but NASCAR rules demanded that at least 500 similar cars be built and made available to the public.

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, conservatively rated at 375 horsepower.

When dropped into the Mustang, it created the Boss 429, a pony car with abundant muscle. To handle the power, the stout “Top Loader” four-speed manual transmission and a 3.91:1 Traction-Lok rear axle were mandatory options. Other features included an engine oil cooler, a trunk-mounted battery, a competition suspension with front and rear anti-roll bars, power front disc brakes, and fat F60x15 tires for maximum traction. The production process required numerous modifications to accommodate the new engine, including cutting and relocating the shock towers. To alleviate the in-house production burden, Ford had the cars converted at Kar Kraft, of Brighton, Michigan; this car carried Kar Kraft number 2073. At $4,087, the Boss 429 was the priciest non-Shelby Mustang to date, and it was available in very limited numbers, with what is reported as an even 500 for the 1970 model year.

The Boss Mustang offered here is a rare preservation example having never required restoration and exhibiting what is reported to be all original except for the battery, gas tank, battery clamp and tires. The 16,700 miles on the odometer are actual for this rare machine. The current owner is only its second, having purchased the Boss 429 from his neighbor in 1975 and then wisely putting the car into indoors storage since the transaction.

Finished in Grabber Blue, it is complemented with White knitted vinyl high back seats and door panels with black dash, carpets and console, plus the simulated woodgrain dash fascia. The Boss exhibits a patina that is commensurate with its overall unrestored condition and largely indicative of a car of its age. This fabulous car has a Deluxe Marti Report as well as additional support of its Kar Kraft number. The Deluxe Marti Report has a complete list of equipment that includes functional front air spoiler, trunk-mounted battery, Drag Pack, Convenience Group, electric clock, Rim-Blow deluxe steering wheel, console, power front disc brakes, power steering, AM radio, Décor Group, deluxe belts/warning lights, competition suspension and tachometer.

This Boss 429 was built in Dearborn on September 3, 1969, two days ahead of schedule and was released on September 17 when it was shipped to Dick Masheter Ford, Inc. on Main Street of Columbus, Ohio. Amazingly, the Deluxe Marti Report shows that the car was not sold until March 15, 1972.

While the Boss 429 appears largely understated, it still is one of the most unique Mustangs ever made. Ford lost money on every car due to the difficulty of fitting of what made the car both truly rare and unique, the 429 powerplant. A rare opportunity is given to own a piece of automotive legend as it rests unchanged from how it was originally conceived.