The aluminum heads had intakes that could swallow a tennis ball, which was great for 200-mph laps around Daytona


In 1969, Ford introduced a limited-production model to the Mustang line. This addition was the Boss 429. It was the most powerful Mustang, and the name referred to its 429-ci engine, which was built in response to Chrysler's 426-ci Hemi and its success in NASCAR.

Named after stylist Larry Shinoda's nickname for Ford president "Bunkie" (Boss) Knudson, the Boss 429s were built for homologation purposes to qualify the 429 engine for the NASCAR race circuit.

The Boss 429 package came with a fully race-prepared 429-ci engine putting out a conservative 375 hp, with ram air induction, an aluminum high-rise manifold, and header exhausts. It included a 4-speed as the only available transmission and a 3.91:1 "traction loc" rear axle. Also included were several other performance items such as an oil cooler, trunk-mounted battery, race suspension, and the best interior Mustang offered.

To meet homologation requirements, Ford had to offer the 429 engine as a "regular" production option and build a minimum of 500 cars for the street. Ironically, Ford offered the new engine in the Mustang, even though the Torino was used in NASCAR. Due to the sheer size of the engine, extensive modification was necessary at the front of the car, which was too narrow. So Ford contracted with Kar Kraft to build the cars.

Staring in January 1969, Super Cobra Jet Mustangs were shipped from the Dearborn plant to Kar Kraft in Brighton, Michigan, where they were converted. The Mustang Boss 429 used scores of parts only fitted to that model. On completion, each car was assigned a KK429 NASCAR production number.

Through July 1969, Kar Kraft built 858 Boss 429s. Each car cost $4,800, and the only option was a choice of color-Raven Black, Royal Maroon, Black Jade, Candy Apple Red, or Wimbledon White. Due to the cost of the conversion, Ford took a loss on each car.

With low production, big power, and a racing pedigree, the Mustang Boss 429 came at the height of the muscle car party and made its mark like no other muscle car could.

SCM Analysis


Vehicle:1969 Ford Mustang Boss 429
Number Produced:1,356 (857 in 1969, 499 in 1970)
Original List Price:$5,000 approx.
Tune Up Cost:$350
Distributor Caps:$43.35
Engine Number Location:KK number on rear of block
Club Info:Mustang Club of America 4051 Barrancas Ave. PMB 102 Pensacola, FL 32507
Investment Grade:B

This 1969 Ford Mustang Boss 429 sold for $248,000 at the Worldwide Group’s Houston Classic Auction in Seabrook, Texas, on May 3, 2008.

The March 1969 issue of Car Life magazine called the Mustang Mach 1 “the first great Mustang.” Four months later they recanted, saying “… but now, the engineers have really done it. The Boss 429. There is even more power and more tire on the ground, but this time the engineers didn’t stop at the surface. They attacked the chassis and added every heavy-duty item they could find in Ford’s stock, plus a few that weren’t. It is, quite frankly, the best enthusiast car Ford has ever produced.”

Those are interesting (if over-the-top) comments from a magazine I always respected. I grew up during the muscle car era, and the feeling on the street was the “Boss 9” was a dog. A good 428 SCJ Mach 1 would usually win a stoplight street fight with a Boss 429, so that is probably the source of the bad rap. Truth is, a good 440 Six-Pack Mopar would beat a Hemi in a similar situation. But get above 60 mph or so, and these race-bred engines really come to life. Car Life saw quarter-mile times of 14.09 seconds at 102.85 mph with their Boss-quite good for street tires and full exhaust (Hi Performance Cars magazine published times of 13.60 at 106 mph that same year).

The secret to the Boss 429’s success in NASCAR was that it was developed with full-throttle superspeedway racing in mind, and the purpose-built aluminum heads had massive, round intake ports that could almost swallow a tennis ball. That design was great for 200 mph laps around Talladega but killed low-end torque and power, which is what a street racer needs. Get out of town and onto the open road, and the Mustang Boss 429 becomes a different car.

The Boss 429 was more than just a huge engine stuffed in a pony car. The revised front suspension, wide F60-15 Goodyear Polyglas tires, and power front disc brakes were engineered around the huge powerplant. Again, Car Life was awed: “The power disc brakes produced deceleration rates repeatedly above one g (32.2 ft/sec/sec) … Suspension changes have brought the handling up to a level approaching an honest race car; and while not exactly in the Corvette’s league, predictability is well within the acceptable range. It’s comfortable. It’s stylish. It comes standard with detail items that enthusiasts usually have to special order, or add later: Oil cooler, battery in the back, suspension modifications, honest spoilers. It’s all there.”

The bargain days are over

Car Life’s conclusion: “The Boss 429, seemingly, has everything, and everything in this case goes for $5,000. That has to be the bargain of the year.”

Well, the bargain days are over. Four years ago, a Boss 429 could be bought for under $100,000. Last January, Russo and Steele sold a Wimbledon White ’69-a former race car with 62 miles on the odometer-for $253,000. On May 17, at Dana Mecum’s Original Spring Classic auction, a Raven Black ’69 from the Dave Christenholz collection sold for $275,000. Top price was brought by a Black Jade ’69 sold by Worldwide Group in May 2007 for $319,000.

Our 1969 feature car was a matching-numbers, one-owner car with 30,000 miles on it, restored on an “as needed” basis after a 30-year hiatus. All the important documents were present, including the build sheet, and the interior was in excellent original condition, a testament to the original owner’s care.

It seems the rest of the world is finally discovering what Mustang enthusiasts have known all along: The Mustang Boss 429 is deserving of the elite status in the marketplace that Hemi ‘Cudas and Challengers and ZL1 Camaros have had for years.

This car was the real deal and priced accordingly.

(Introductory description courtesy of Worldwide Group.)

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