1969 Ford Mustang Boss 429: The Boss 9 Rules the Day
After several years of adding to his vast collection of factory muscle cars, Tacoma collector Gary McKay discovered one of the rarest muscle cars ever produced – a Raven Black 1969 Ford Mustang Boss 429.
By 1969, the Pony wars between the big three were at a frothing boil. The catch phrase “Win on Sunday, sell on Monday” became scripture to the Detroit manufacturers. Whoever could build the most desirable large-cubed engine powering the sleekest vehicle on the racetrack would win customers on the showroom floor. To the Ford enthusiasts and muscle car aficionados alike, the 1969 Mustang Boss 429 is a legend.
Only 859 of the “Boss 9s” were produced in 1969. McKay’s Raven Black Mustang was born on April 17th, 1969, at Ford’s Dearborn, Michigan plant. All 859 Mustangs that were granted the special Boss status were then sent to Kar Kraft in Brighton, Michigan for alteration. Kar Kraft was contracted by Ford to handle its specialty-constructed vehicles. The 429c.i. engines would not just drop into the engine bay – alteration was necessary to receive the massive motor. The wheel wells required widening, and the suspension was altered to accommodate the weight. The Kar Kraft engineers employed many other methods of construction for this limited production run.
What makes this Mustang unique compared to all the other 1969 Mustangs produced is the obvious power plant. The 429 was born of the 385 big block, with 4-bolt main caps, a forged steel crank, and forged steel connecting rods. The bottom end of the engine is solid as bedrock. With a firm foundation, Ford focused its attention on the cylinder heads. This is where the magic happens. The semi-hemispherical combustion chamber aluminum heads, combined with the high-rise aluminum intake and 735 cc Holley Carburetor give the engine outstanding lung capacity and fuel burn. Ford, like many of the other automotive manufacturers at the time, tended to underrate their performance numbers. Factory numbers report that the Boss 429 produced 375 horsepower and 450 lb-ft of torque. Actual horsepower numbers have been reported well above the 500 mark.
When he acquired this Mustang nearly seven years ago, McKay reports that it was in a great state of preservation. By his standards, it still required a full concourse restoration and that’s what took place. The interior down to the carpet is factory original, so no work was needed there. Any parts of the vehicle that needed replacement were all NOS components. After its repaint, the Mustang was put back to original condition, and the best part of the story is, it only has 18,000 original miles. This pony car is still Boss.