1970 Ford Mustang "Boss 429" Fastback

Vehicle Details

429ci OHV Q-Code V8
Holley 735 CFM 4-Barrel Carburetor
375bhp at 5,600rpm 
4-Speed Close-Ratio Manual Transmission
Competition Coil Spring Front Suspension and Semi-Elliptic Rear Leaf Springs with Traction-Lok Live Rear Axle 
Power-Assisted Front Disc and Rear Drum Brakes

*Authentically Restored and Presented
*Most Sought After Performance Mustang
*Show Quality Presentation Throughout
*Rare opportunity to be the "Boss"


It is simply the most awesome regular production Ford Mustang ever created and it really deserves the name "Boss". Created as an outlet to market their mighty NASCAR 429 engine, which was actually used on the track in the Torino-based Talladega hardtops, this was not your standard 429 V8 with a few tweaks to make it go faster. Derived from Ford's "385" program, which was the last generation of big-block Ford engines ever developed, the Boss 429 would use four-bolt mains, forged steel connecting rods and a heavy duty forged steel crank shaft. Special cast aluminum heads were developed to mount to the block using what Ford termed "crescent" combustion chambers that were basically a modified hemispherical style system. These heads were mounted using the "dry-deck" method, which meant they were mounted metal to metal without a head-gasket. Each individual oil and water passage were sealed tightly using "O" ring style seals which proved to be very effective. 

When first developed, the Boss 429 engine used hydraulic lifter camshafts, but for 1970 a more secure system of mechanical lifters was incorporated into production. Another improvement that year was a modified exhaust system that reduced any flow restrictions to a minimum. Despite these improvements, Ford did not cite any increase to the horsepower ratings. Fuel induction for the Boss 429 was achieved through the use of a single, 735 CFM four-barrel carburetor supplied by Holley, which was mounted atop a specially ported aluminum intake manifold. 

NASCAR rules dictated that components had minimum production numbers to be properly homologated into the racing program, but NASCAR did not require that the components be made available to the public in the same configuration as raced. Thus, the production Talladega received a 335bhp version of the "Q" code 428 ci V8 matched to a C6 automatic transmission, which early competition versions were fitted with the FE block 427 ci side-oiler with the Boss 429 being introduced later in the season. 

There were major production woes to be addressed with the production of the Boss 429 Mustangs. Simply put, in pure stock form, the 1969 Mustang's engine bay would not accept the Boss 429 engine! Extensive hand re-working was needed for each vehicle and Ford turned to an ally in the Detroit area to help create these most powerful pony cars ever—Kar Kraft. The association of Ford with Kar Kraft dated back to 1963 and beginning of the GT40 project that would lead Ford to the winner's circle at the 24 Hours of Le Mans. Kar Kraft was prepared to do whatever was needed to get a car put together and deliver the ultimate in performance. With the Boss 429, or the "Boss-9" as it is often referred to today, each car was specially prepared as it came down the assembly line at the Rouge assembly plant in Dearborn. But there were a lot of parts missing from these special Mustangs when they reached the end of the assembly process, most importantly, the engine and transmission. 

These incomplete cars were then transported in special carriers to the Kar Kraft facility. There they entered their second assembly line. First order of business was a rebuild of the engine bay, removing the strut towers and inner fenders, then a relocation of the front suspension mounts so as not to interfere with the mounting of the engine. Also removed from the engine bay was the battery, relocated to the trunk. A rear sway bar was fitted to help keep the car going in a straight-line during acceleration and on the road maneuvers. Engines were prepared at Ford and shipped to Kar Kraft where special mountings had to be built before the mighty V8 was shoe-horned fitting snugly under the hood. 

Other amenities added to the Boss 429 including the 3.91:1 "Traction-Lock" rear axle, and to keep track of the high-revving engine, a tachometer rated at 8,000 rpm was installed. Helping to keep the engine at an even operating temperature, an oil cooler system was added and finally a manually adjustable air-flow hood-scoop was mounted to the hood. Keeping the weight to a minimum, special ornamentation was missing from this car with a simple decal added to the front fenders proclaiming the car as the "Boss 429". The only other visual cues to this super Mustang's identity were the Magnum 500 wheels and a front spoiler to aid in providing a bit of downward force. One final touch was added, the application of a small silver sticker with the letter "KK" and found control numbers applied to the rear face of the drivers door either below the data plate for 1969 models, or the Federally required sticker on the 1970's. 

The final product was capable officially of 375 horses at 5.600rpm, which were artificially reduced so as to try and keep the insurance companies from going off the charts with premium payments and possibly trying to quell an uprising from government regulators. However, from contemporary tests of the day, it was shown this engine could easily attain up to 500bph at 6,200rpm, and with a few minor modifications, significantly more! 


According to our consignor, he purchased this car in Kentucky from a Mr. Taylor who claimed to be an heir to the Taylor Ice Cream Machine Company. At the time of Mr. Taylor's purchase in the early 1980s, this Boss 429 was complete and running but had seen better days. Mr. Taylor sent his prized Mustang to a restoration shop that in the long run took his money, took the car apart and then disappeared. In the late 1990s, our consignor was in the vicinity to purchase an elusive Ford 427 "Side-Oiler" engine when he got wind that there was a Boss 429 with an owner who really wanted to see the disassembled car go away. After some quick negotiations, "Boss-9" KK2481 was on its way to the consignor's shop where it was treated to a full rotisserie restoration. During this process it was found that the body was in remarkably solid condition with only a minimum of body repair needed. Attention to authenticity was paramount in the restoration of the beauty including making an exact match for the Grabber Blue exterior. 

Mechanically the car seemed to run out quite well and all of the originally installed components were given a total rebuild, again paying strict attention to factory specs. Original markings that were still visible were replicated during the lengthy process. 

Once complete Boss-9 KK2481, was delivered to noted Boss 429 authority, Kevin Manely in Cannon Falls, Minnesota. There were only a couple of very minor details to which attention needed to be paid. Each was immediately addressed and with the Boss brought back to the factory levels of fit, finish, and overall quality as delivered new from Kar Kraft. 

Occasionally shown but carefully kept, this Boss has driven only the 15 miles on the odometer since the restoration was completed nearly 10 year ago. The paint appears to be without issue as do the sheet metal panels lined up and gapped to the tolerances as seen from the factory. As stated above, the Grabber Blue paint, reflected by code "J" on the build tag, is a perfect match for that high-impact color that defines the era into which this car was born. One of the few exterior differences between the 1969 and 1970 Boss 429's was the hood scoop was painted matte black, which has been correctly captured on this example. Looking inside the car, the interior's white Comfortweave vinyl bucket seats and all other appointments looks just as it must have when delivered new from the factory, down to the plastic covered floors—even the pedals are wrapped in protected plastic. All the glass is pristine with proper factory markings and factory applied decals are in place including the inspection stickers that were applied to the car as it rolled off the assembly line. 

As fans of the Boss 429 celebrate this mighty Mustang's 50th Anniversary this year, the offering of this car allows you to buy effectively a brand-new example, half a century after this beast first roared to life.