The 'Big Three' automakers had a self-imposed ban on racing, but by the mid-1960s, this agreement had collapsed. By this point in history, most American auto manufacturers were providing factory support to supposedly independent racing teams. It was clear that showroom sales were tied to racing success, and Ford did all they could to maintain its edge following David Pearson's 1958 NASCAR championship win. Since NASCAR disapproved of the exotic SOHC 427, Ford's Tunnel-Port 427 soldiered on through 1968. A new engine was needed for the Torino Talladega and Cyclone Spoiler bodies. According to NASCAR rules, at least 500 road cars were needed to be produced and made available to the public.
The Boss 429 was based on Ford's 385-series V8 engine and was given aluminum cylinder heads with hemispherical combustion chambers, an aluminum high-rise intake, a 735-cfm Holley carburetor, 10.5:1 compression, header-style exhaust manifolds, a four-bolt main block and more. Instead of installing it in the midsize Cyclone and Torino like their NASCAR counterparts, Ford placed its potent engine into the smaller Mustang. Standard equipment included a 'Toploader' close-ratio four-speed transmission and a nine-inch Traction-Lok rear end with 3.91:1 gears, plus an engine-oil cooler, a trunk-mounted battery, competition suspension with front and rear anti-roll bars and staggered rear shocks, power front disc brakes, chrome Magnum 500 wheels and wide F60X15 tires.
To make room for the essentially hand built Boss 429, extensive modifications were made including the cutting and relocating of the front shock towers. Ford shipped the cars for conversion to Brighton, Michigan's Kar Kraft for completion.
As was common practice in that era, Ford conservatively rated the 'street' version of the Boss 429 Mustang at 375 horsepower. Priced at $4,087, the Boss 429 was the priciest non-Shelby Mustang to date. Production was limited to 859 examples (including two Boss-Cougars) for 1969. 500 more examples followed a year later (including two 'Quarter Horse' Boss/Shelby hybrid prototypes) prior to the cancellation of Ford's corporate racing program.
Ford offered the Boss 429 in five colors including Calypso Coral, Grabber Orange, Grabber Green, Grabber Blue and Pastel Blue. Only 18 Boss 429s were painted in Pastel Blue, and only two of them had white interior upholstery.
This example, chassis number KK2290, has had four owners since new. It was given a complete, ground-up restoration under the prior owner, who acquired it from Joe Flowers in 2001. The current owner acquired the car in March of 2008. The car is currently equipped with the factory-correct emissions equipment and rides on a new set of correct Goodyear Polyglas tires.
In 2012, this vehicle was offered for sale at RM Auction's sale in Scottsdale, Arizona. It was estimated to sell for $175,000-$225,000. As bidding came to a close, the car had been sold for the sum of $170,500 inclusive of buyer's premium.