Ironically, what makes the 1969 Boss 429 Mustang so valuable to muscle car collectors was the very reason it was such a failure at the drag strip. Ford fans thought they finally would beat Chevrolets and Mopars at the dragstrip with the high revving semi-hemi Ford 429 motor. But the the monster motor that was so effective in NASCAR stock car racing could not make power off the line. In the “win on Sunday, sell on Monday” world of drag racing, the Boss 429 Mustang did not sell well enough to keep the program going. After two years, 1969 and 1970, Ford stopped producing the Boss 9. That is exactly why they are so valuable today.
The 1969 Boss 429 Mustang today is worth more to collectors than the vaunted Hemi Cuda or even its Ford cousin, the Shelby Mustang. Why? Because they only made 859 of them that year, they are worth twice what a Shelby KR convertible would bring in today’s collector car market.
This week, a Raven black 1969 Boss 429 Mustang is being offered for sale by a private seller in the Twin Cities area of Minnesota. This one is especially valuable because they only made 93 Boss 9’s in Raven black, the rarest of any of the five possible Boss 9 colors. (Follow this link to view more photos and read the ad copy.) It was originally sold by a dealer in Michigan. The seller says it still has the original paint and interior.
Although it seems to be a survivor, the seller says the engine compartment was freshened back to original. Having been maintained in a climate control facility, it is in amazing condition. (You can view a photo bucket of pictures, which include photos of the undercarriage and detailed shots of the interior.) The seller says it was rustproofed at the dealer back in the day. In this instance it may have preserved the car along with its history of careful storage.
The 1969 Boss 429 Mustang has just over 8,600 miles showing, and is fully documented with Marti report, build sheet, original license plates and history since new.
History of the 1969 Boss 429 Mustang
Although Ford raced this motor in the Torino Talladega in NASCAR, for homologation, they believed they would sell more cars if they put the Boss 9 motor in their most popular seller, the Mustang Pony car. NASCAR required that for any motor to be run in NASCAR competition the factory had to sell at least 500 cars equipped with that motor. While Ford dominated NASCAR in 1969 with the Boss 9 motor, its greatest gift to the collector car market was its NASCAR KK 1969 Boss 429 Mustang muscle car.
Kar Kraft, a Detroit area after market shop, had the difficult job of fitting the massive 429 big block underneath the hood of a Mustang. The task involved having to widen the space between the shock towers and move the front suspension mounts in order to make room for the engine. Although Ford rated the Semi Hemi engine at 375 horsepower it was pretty much assured that it was really around 500 horsepower. It was a handfull to pilot on a road course, but in a straight line it just couldn’t be beat. With the right setup it would do 10-second quarter-miles pretty consistently. That said, you can just imagine how fast the Boss 9 was when it had the Buddy Bar Dual-4’s package like this one. That’s what makes this car so special.
In order to get the KK Boss 429 motor certified for NASCAR competition Ford had to produce a street version of a car that used the Boss 429 big block Semi-Hemi engine. The engine was a monster. Ford engineering used four-bolt mains, and a forged steel crankshaft. The aluminum heads had big ports, and staggered valves with crescent shaped combustion chambers. It was topped by a 735 cfm Holley 4-barrel with ram air and an aluminum high-rise manifold. You also got factory headers. Retail for the 429 motor alone was $1,200.
The Boss 9 only came with a 4-speed transmission and a 3.91:1 Traction-Lok rear end. The package came with an oil cooler, trunk-mounted battery, and heavy duty suspension with both front and rear stabilizer bars. The interior decor package included an 8,000 rpm tach. Air conditioning and automatic transmission were not an option.