A 1970 Ford Mustang Boss 429 with just 4,028 miles on the odometer has surfaced on Bring a Trailer, and it’s already attracting serious money. Finished in Grabber Blue with a white interior, this remarkably well-preserved muscle car is one of approximately 500 Boss 429s built for the 1970 model year.
Its rarity also makes it one of the most sought-after muscle cars of the era. Originally developed to satisfy NASCAR homologation requirements, these machines featured a massive 7.0-liter V8 that required extensive modifications to fit beneath the Mustang’s hood.
This particular example, identified by Kar Kraft serial number KK2288, has stayed with its third owner in Northern California for nearly 40 years. Its unusually low mileage is supported by documentation from Boss 429 expert Bob Perkins, who examined the car decades ago.
With the auction scheduled to end on October 12, collectors still have a chance to acquire an exceptionally low-mileage example of Ford’s legendary muscle car. Whoever wants to take it home will need seriously deep pockets.
Built To Bring Ford’s NASCAR Engine To The Streets

The Boss 429 wasn’t simply a regular Mustang fitted with a larger engine. Ford’s specialized V8 was so wide that Kar Kraft had to modify the engine bay, reposition the shock towers, and revise the front suspension to make everything fit.
Those changes gave the Boss 429 a distinctive appearance, complete with its enormous hood scoop and competition-oriented suspension. The extensive reengineering also explains why Ford relied on Kar Kraft rather than building these specialized Mustangs entirely on its regular production line.
The engine itself was equally special, featuring aluminum cylinder heads with crescent-shaped combustion chambers designed for high-performance racing applications. Despite its impressive hardware, Ford officially rated the 7.0-liter V8 at 375 horsepower, delivered through a four-speed manual transmission and a 3.91 Traction-Lok differential.
A Remarkably Original Survivor

Unlike many valuable muscle and pony cars that have undergone extensive restorations, this Boss 429 is presented as a largely original survivor. Its Grabber Blue exterior is complemented by white vinyl upholstery, an unusual combination that gives the car plenty of visual character.
Factory equipment includes power steering, power-assisted front disc brakes, 15-inch Magnum 500 wheels, a Hurst shifter, and a tachometer. The interior also retains its woodgrain trim, center console, and AM radio.
There are a few details worth noting, including a small paint touch-up and a visible paint drip near one of the Boss 429 decals. The rear spoiler and Sport Slats were added later, while historical documentation records engine-bay detailing and the reinstallation of emissions equipment around 1988.
Just 17 Miles Added Since The Late 1980s

According to Perkins’ documentation, the Mustang had accumulated approximately 4,011 miles by 1988. Its reported total now stands at 4,028 miles, meaning it has traveled only about 17 additional miles since then.
That remarkably limited use helps explain the car’s collector appeal, although prospective buyers will naturally want to examine its documentation and condition carefully. The sale includes a Deluxe Marti Report, owner’s manual, and Indiana title.
How Much Will This Boss 429 Bring?
Low-mileage Boss 429s rarely appear at public auction, particularly examples accompanied by documentation supporting their originality. That makes this Grabber Blue Mustang an interesting opportunity for collectors looking for a largely unrestored example.
The auction’s $300,000 bid (at the time of writing) is already serious money, but it isn’t a confirmed sale price. Whether the Mustang climbs higher will depend on collector demand, its reserve, and how bidders value its originality.
Whoever takes it home will face a familiar classic-car dilemma. Should they preserve those precious low miles or finally let that massive V8 stretch its legs?
