Autoblog and Yahoo may earn commission from links in this article.Meet the BossOver the course of the Mustang's 62-year history, many special and limited editions have been made. Some are rarer than others, and admittedly, some aren't really worth the asking price. However, the Boss 429 is very much deserving of its legendary and iconic status.Its rarity isn't the only reason why the Boss 429 earned its status. Like many cars that have been crowned iconic, it has an interesting backstory.ReserveMotorworks/Bring a TrailerThe BackstoryAccording to Classic.com, the Mustang Boss 429 has a market value of $383,117, which makes it more expensive than a brand-new GTD before options. It's well justified, though, as this car has a story to tell. In 1969, Ford unveiled two Boss Mustangs, namely the 302 and the 429. The 302 was produced 8,641 times from '69 to '70, but the 429? Only 1,359 were ever made during the same time.AdvertisementAdvertisementThe one we found on Bring a Trailer is an example from 1970. Draped in Grabber Blue, it currently shows 30,000 miles on the clock, and at the time of writing, the bid stands at $225,000 with 8 days to go. This car has exchanged hands a few times and has seen restoration work over the past 50-odd years. It also has a good number of options fitted to it, too. It comes with competition suspension, a close-ratio four-speed manual, and a Drag Pack that throws in a Trac-Lok limited-slip diff. Oh, and there's air-con, too.The OfferSpecificationDetailMakeFordModelMustang Boss 429Year1970Mileage30,000 miles shownEngine429ci Boss V8Power375 horsepowerTransmissionFour-speed close-ratio manualDrive typeRear-wheel drive with 3.91 Traction-Lok differentialExterior colorGrabber BlueInterior colorWhite Corinthian vinylWheels15-inch Magnum 500-styleSuspensionCompetition suspensionBrakesPower-assisted front disc, rear drumSteeringPower-assistedCurrent bid$225,000Interested in this car? View the listing here.ReserveMotorworks/Bring a TrailerWhy it's SpecialThe Boss Mustangs were born out of necessity for Ford. At the time, the company wanted to race in other series, and that meant the need to homologate. The 302 was meant for the Trans/Am series, while the 429 was for NASCAR. Now, the Boss 429 Mustang never raced in NASCAR, but rather, the engine fitted to it did. Ford needed to build at least 500 road-going versions to allow the 429 engine for competition.Final assembly was done by Kar Kraft, as regular production lines couldn't accommodate the whopper of its 7.0-liter engine. For those familiar with Ford's motorsport history, Kar Kraft is the same firm that helped develop the GT40, so it's safe to say that the folks there know what they're doing. To fit that engine, the front end had to be modified, along with additional handling upgrades to help it turn. As for the engine, it made 375 hp and 450 lb-ft of torque, although it's been disputed that it actually made more. This was pre-smog-and-oil-crisis America, so it might actually hold some weight.AdvertisementAdvertisementWith the extensive re-engineering that went into it, the 429 cost about twice as much as a base six-cylinder Mustang from back in the day. Still, it was bound to be a rare beast and collector's item. With the options fitted to the one that's for sale, one could say that its asking price is well worth it.ReserveMotorworks/Bring a TrailerReserveMotorworks/Bring a TrailerView the 12 images of this gallery on the original articleThis story was originally published by Autoblog on Aug 17, 2026, where it first appeared in the Car Buying section. Add Autoblog as a Preferred Source by clicking here.