Eric English
February 3, 2010
Photos By: Jim Smart

Source Interlink Media archives, and owners

For understandable reasons, most enthusiasts immediately think Mustang when the phrase "Boss 429" is tossed around in conversation. Narrowing the definition even more, it's likely that the term elicits visions of beautifully restored stock Boss 429 Mustangs, as that's where most of the activity is concentrated in today's market. Certainly the '69 and '70 Boss '9 Ponies are a crown jewel of many a Ford lover's collection-or dream collection for most of us, and yet the biggest Boss has a tradition far beyond the 1,356 (1,358 w/2 Cougars) Mustang SportsRoofs that rolled through Kar Kraft's Brighton, Michigan, assembly line beginning January 15, 1969. We'll be exploring the legend of Ford's Shotgun big-block over the next several pages, and most of our featured vehicles will be anything but chalk-marked stockers-just what you'd expect from a magazine whose title leads with "Modified," right?

At its elemental best, the Boss 429 should be described as an engine, not a car, and is without a doubt the most exotic powerplant installed in a production Ford of the era. Of course the reason for a street version at all stemmed from Ford's primary goal for the near-exotic derivative of the 385 series engine-NASCAR stock car racing. While admittedly less of a force than it is today, stock car racing had gone big time by the late '60s, and championship caliber performance garnered prestige and showroom sales for the manufacturers at the top of the heap. In order to run the Boss 429 in its stock cars, Ford had to manufacture at least 500 street versions to homologate (legalize) the engine for competition. Obviously the requirement didn't mandate that the street engine be installed in the same model as that being raced, else the Boss 429 the car, would be a Torino or Cyclone. An educated guess would say the movers and shakers at Ford corporate, including big chief Bunkie Knudsen, likely decided that the marketing hype for their new supercar would be best directed at the hotly contested ponycar/musclecar market. Anyway, Ford subcontractor Kar Kraft was tapped for conversion from run of the mill Mach 1, to aluminum-headed monster, and the rest is history.

As it turns out, history has been kinder to the Boss 429 Mustang than the press of the day. Today, the car is revered in most circles, and yet most of us know that as constructed, the biggest Boss was something of a dud in terms of performance. Leading up to the car's introduction, the automotive press was drooling with great anticipation of a "12-second Mustang," but in reality, a stock Boss 429 Mustang never even broke into the 13s in any period test we've seen. More mainstream 428 Cobra Jets handily outran the B9s, and the car was almost universally panned by enthusiast magazines of the day-deemed a "stone" by some. In the end though, the lack of stock performance has done little to diminish the significance or desirability of the Boss 429 Mustang-it remains one of the most unique cars ever built by the Ford Motor Company. It was truly purpose-built, even if that purpose is sometimes a bit misunderstood.

Stock Cars
If the Boss 429 was a failure as a street supercar, it certainly prevailed in the discipline it was intended for. Nineteen sixty-nine would be a banner year for Fords in NASCAR, a double whammy result of the new Talladega and Cyclone Spoiler II bodywork, combined with B9 power. While the aero bodies were legalized in time for the Daytona 500 on February 23, 1969, the first race for the Boss 429 was a month later at the Atlanta 500. Cale Yarborough was victorious in a Wood Brothers Cyclone Spoiler II, followed in Second Place by David Pearson in a Talladega, and Ford/Mercury would go on to win 30 of the 54 races that season. Ford earned the manufacturer's championship, and David Pearson walked away with the driver's championship. You could call it near-total domination.

Nineteen seventy proved disappointing compared to the year prior, with Ford products scoring just 10 NASCAR victories, though Ford pilot James Hylton did place third in the driver's points chase. Some of the trouble was undoubtedly the dismissal of Ford President Bunkie Knudsen in September 1969, who had been a strong supporter of the various racing programs at Ford. Not long after, it was announced that the racing budget would be cut across the board for 1970. Simultaneously, the Chrysler winged cars were either introduced (Plymouth Superbird), or dialed in (Daytona Charger), with a combination tough to overcome.

Ford would completely pull the plug on corporate support for stock car racing in late 1970, so perhaps it is surprising that 1971 saw 15 FoMoCo NASCAR wins and drivers in the second and third spots in the driver points tally behind the wheel of a Ford and Mercury respectively. The end of the Boss 429 was drawing near in 1972 and 1973, as rules changes would soon begin to squeeze out big-blocks across the board. While manufacturer and driver championships would elude Ford teams during this period, David Pearson was a notable highlight in the Wood Brothers Mercury Cyclones. Both years saw this skilled driver run just a partial schedule, but when Pearson showed, he truly put on a show. In 1972, Pearson won 6 of the 14 races he entered, and in 1973, won 11 of the 18 entered. That latter tally was more wins than any other driver that year, but Pearson's inconsistent participation left him in 13th in the driver's points chase, while 1973 season champion Benny Parsons won just once all season.

Shifting Gears
Boss 429s were run in a variety of drag race environs, from stock classes to Funny Cars. None really set the world on fire, though there were glimmers of success here and there. Pro Stock and its immediate predecessors seemed to showcase the engine's best attributes, where the Boss was free to fill up on the compression, carburetion, and camshafts that weren't allowed in Stock and Super Stock. Factory backed Mustangs, Cougars, and Mavericks, were driven by the likes of Ed Schartman, Butch Leal, Dave Lyall, Dick Brannan, Wayne Gapp, Al Joniec, and others. While these Boss 429s didn't prove a dominating force in the end, they were competitive, with some pretty wild rides being the result.

Ohio George Montgomery may have been the most successful Boss 429 drag racer of the early years, or at the very least you can say his car was the most unique. Montgomery scored several national wins during the early '70s in his '69 Mustang-bodied twin-turbocharged Boss 429 AA/GS car, known as the Mr. Gasket Gasser. Eventually it was legislated out of NHRA competition, but as time went on, the Boss 429 and its familial descendants would prove their worth in a variety of drag classes-including Pro Modified and Pro Stock. More specifically, it was in early 1980s IHRA Pro Stock competition that the Boss really started to show its stuff. Ronnie Sox won the 1981 championship in a Boss-based Mustang, and Rickie Smith did likewise in 1982-with power from a Jon Kaase behemoth. The trend would continue throughout the decade, including Bob Glidden's remarkable five-straight NHRA Pro Stock championships with Boss descendents. Even today, IHRA Pro Stock records for ET and top speed are both held by 823-inch Kaase Hemi Mustangs-the e.t. record going to Frank Gugliotta with a 6.251, and the speed record to Brian Gahm at 223.95 mph.

Butch Leal was a very young man when he signed on to drive Mickey Thompson's Thunderbolt in 1964, and despite deviating to Chrysler Hemis a short time later, he was back with Thompson in this front cover picture from the July 1969 issue of Car Craft. The Car Craft article mentioned the featured Boss 429 was a Super Stocker, but Leal told MM&F that he never raced it in this class-instead, running in classes that preceded the official Pro Stock division in 1970. Leal remembers much about the beautiful blue '69, including that it was painted at Bill Stroppe's shop. Leal swears that the car was wearing the dual 4s when he picked it up at Galpin Ford, but before long, it wore a custom tunnel ram that Leal had Buddy Bar cast up. Leal describes his Boss 429 as real competitive in 1969, and says he could run with the west coast Hemi Darts of the day, such as those raced by Dick Landy and Bill Bagshaw. Leal ought to know, as he'd campaigned a Hemi Dart just prior to linking up again with Thompson for the Boss 429. "I did a lot of development work on that car" says Leal, "seems like I had it torn down every week, trying new things and working it over." The basis for the bottom end was the stock Boss block, a Grand National crank, aluminum rods, and Mickey Thompson pistons. Up top, Leal would eventually run fully hemispherical chambers in the heads (like the NASCAR pieces), and the aforementioned tunnel ram. "I've never told anyone else about this," laughed Leal as we conversed with him for this story. "To make the Boss really run good, I finally took a cam blank to Racer Brown, and asked him to grind me a cam like I ran in the Mopar Hemis, we called it the 590 cam. I also changed to the Chrysler firing order." Leal also reported running a lightweight aluminum Chrysler four-speed with a 2.66 low gear, and a 4.88 geared Dana 60 rearend. "One thing I learned from Don Nicholson was dialing in the chassis. The Boss hooked so good that I kept blowing pinion gears out of the front of those nodular cases in testing down at Lions (Long Beach). The Dana took care of that." In the end, Leal says the Boss program came to an end when Ford pulled out of racing, and picked up many of the factory items from Thompson's shops.

Street Disappointments . . . Why?
Despite NASCAR success, it's still hard not to be disappointed by the Boss 429's performance in street and near-street guise. Tests of the day showed very low 14-second performance for showroom examples, which really isn't bad for a stock musclecar, just off the mark for a car with such exotic hardware. Consider the sheer cubic inches, the impressive top end, mandatory four-speed, 3.91 gears, trunk mount battery, big F60-15 tires, and it's no wonder the magazines expected more. The inevitable question of why, was covered in a couple of articles in the day.

The Nov. 1969 issue of Hi-Performance CARS magazine had two interesting articles on Boss 429s. One was a story on Wayne Gapp's AHRA-style '69 Mustang gas Funny Car, the other, and our focus here, was a report on the progress of Tom Larkin Ford's '69 Boss 429 B/stock racer, entitled Stone Pony or Strip Stallion?. The article articulated the difficulties in getting the Boss to be competitive in class-the record holder at the time being a '67 427 Fairlane at 11.85 at 119 mph.

Several obstacles were discussed by author Roger Huntington that are enlightening. First, it's pointed out that as delivered, the Boss had pretty sloppy tolerances, i.e. chamber volumes, crank balance, and so on, requiring an extensive blueprint job. Next came discussion of the weak hydraulic camshaft which all early S-code engines (and early T-code engines) came with. The mechanical cam Ford substituted thereafter was clearly the way to go in the eyes of the Larkin crew and other sources we've seen. Also mentioned was the handicap that the comparatively mild 10.5 CR and 735cfm Holley dictated, as in class, much of the competition had more of both, yet rules did not allow changes from OEM specs.

More factory hampering appears to have come from the mean-looking Boss hoodscoop, which in reality was a functional failure at speed. Again in the stock classes, rules prevented altering the scoop, but by removing the air cleaner/hood seal, the Larkin car picked up an unbelievable half a second and 10 mph. Rather than feeding the desired cool air, the scoop seemingly choked the engine for air at high speeds, and removing the assembly allowed unlimited underhood air for the engine to inhale. Moral to the story-hot air is better than no air. Unfortunately, the competition had more effective cold air induction, again placing the Boss 429 at a disadvantage. At the time of the article, it was noted that the Larkin Boss had run a best of 12.09 at 118, or about 0.25 off the national record. In many ways, the CARS story pointed to encouraging signs that the Boss 429 had big potential, particularly in classes where carburetion, compression, and hoodscoop design were unlimited.

Yet another enlightening story appeared in the Jan. 1970 issue of Car Craft, which paralleled some of the CARS criticism, and highlighted additional problems. Everyone lambasted the original hydraulic cam, but CC pointed to a heavy valve package, which, particularly when teamed with the hydraulic cam, resulted in valve float above 5,400 rpm. Considering that the cylinder heads were designed to function all day at 7,200 rpm in stock car competition, such rpms were way short of optimal. As well, the 429 internal dimensions of a 4.36-inch bore and 3.59-inch stroke inherently means the engine isn't a torque monster, so rpm capability is critical.

Car Craft also roundly criticized Ford's Product Acceptability Standard, or P.A.S, claiming this corporate policy mandated that all Fords, no matter their intent, "must start when the engine is hot, start in cold weather, idle, run in traffic in Fourth gear, and run smoothly at 20, 60, or 80 mph, just like a Lincoln Continental. In addition, the P.A.S. demanded that the engine compartment, passenger compartment, and overall noise levels must not exceed a certain maximum." Author Terry Cook pointed out that high-end Mopars weren't saddled with such limitations, and added that "until Ford loosens its P.A.S. for performance cars, it will continue to take a back seat to GM and Chrysler in performance." Car Craft went on to review separate performance efforts being made by Foulger Ford, Dave Lyall, and Wayne Gapp, and ended with a telling Boss 429 test session on the engine dyno at Crane Cams. When the best pull yielded 386 hp at 6,000 rpm with Ford's updated mechanical cam and dyno headers, Car Craft concluded "the Boss 429 is touted as a performance engine, but dyno figures don't support this claim to date." Ouch!

When was the last time you saw a Boss 429 Mustang with the front wheels sky high? Ford dyno technician Dave Lyall did it regularly in 1969 and 1970, actually campaigning two similar-appearing '69 SportsRoofs supplied by Ford. One was a preproduction '69 durability test car that Lyall turned into a stripped out AHRA match racer, the second was a legit Boss 429 that first ran SS/D, then "heads up Super Stock" (AHRA predecessor to Pro Stock), and NHRA Pro Stock. Both cars ran Boss 429 engines as Lyall helped Ford engineer Wayne Gapp with development work on the new race engine, and both cars would also be updated with '70 sheetmetal. Lyall explained, "We couldn't quite get the Boss to run at the national record in Super Stock, so we eventually made it a Pro Stocker. I remember the first honest to goodness "Pro Stock" race at the 1970 Winternationals. Unfortunately, we broke, so obviously didn't do very well. Not long afterward we went to the Super Stock Nationals at York US 30, and did quite well. I lost in the quarterfinals to eventual winner Ronnie Sox in his Hemi 'Cuda, he'd just outrun me over the last 300 feet or so. As the top loser, I came back into the mix when one of the remaining cars couldn't make the call, and Ronnie did it to me again-obviously he mile an hour'd better." (Dave Lyall photo collection)

Kaase Boss Nine
Big news for classic Ford enthusiasts occurred in the last year, as Jon Kaase Racing Engines released brand-new Boss 429 cylinder heads, rocker arms, valve covers, and intake manifolds. Unless you've been hiding under a rock for the last 20 years, you'll recognize Kaase's name as one of the preeminent big-block Ford builders, specializing in the mountain motors of IHRA Pro Stock. Kaase engines can be credited with more than a dozen IHRA championships, but Kaase began the hard-core phase of his Ford experience in 1977 working for one of the greats, Dyno Don Nicholson. More recently, he's received positive ink for winning the Engine Masters Challenge four times (2003, 2004, 2008, and 2009), the most recent win coming via a 400-inch Cleveland.

The genesis for the new Boss Nine parts came from Kaase's desire to build a Boss 429-based engine for the Challenge. "The problem was that original Boss parts are hugely expensive and relatively fragile as well," says Kaase. From the start, the idea was to build parts that could be used as replacements for original Boss 429 components, or used to easily build a Boss from scratch. The latter wasn't the case prior to the new parts, as a Boss block was almost a requirement in order to use the heads-if you could find them. Boss blocks utilize unique oil galleries and drain holes which match those in the Boss heads, lubricating the rocker assemblies through the rocker stands. Non-Boss 429/460 blocks don't have these features, as the rocker system on conventional 385-series big-blocks is oiled through the pushrods. While tapping into the lifter oil gallery on a standard block, and running plumbing in the lifter valley to the Boss head oil galleries is technically possible, and has been done, there are additional issues to overcome. Clearance problems with a standard block are generated by the Boss' steeply angled exhaust pushrods as well.

A far better option are Kaase's new Boss Nine heads, which, while stock-appearing from the outside, are revised in ways that allow them to be easily used on all 429/460 blocks. It's a simple bolt-on operation. Also revised are the CNC-machined combustion chambers-now more detonation resistant, and smaller to allow reasonable compression with flat-top pistons. More important changes were incorporated into the intake- and exhaust-port designs, as well as the rocker-arm geometry. Actually, the entire rocker system is greatly improved over original, and is specific to the Kaase heads-meaning no interchange with the original Boss 429 rocker system.

All other parts do interchange however, meaning you can run a Kaase intake on stock heads, and so forth. You could even bolt stock exhaust manifolds to the new heads, whereupon the "Modified" part of us will ask, "why let 400cfm intake/300cfm exhaust flow potential go to waste?" Throw a set of headers on her, slip in a stout cam, and let it rip! In reality, there is probably a market for folks who need a set of heads for their otherwise-stock Boss 429 Mustang, but we look forward to seeing what people do with the new Kaase parts to really take advantage of their potential. How about a NASCAR Torino clone? How about a Pro Stock Maverick?

Kaase Cylinder Head
Rocker stands aren't used on the new Kaase heads as they were originally, rather the new Boss Nine head has a cast in boss that does away with stands all together. The exhaust rocker is slightly longer, taking some angle out of the pushrod, while also moving the pushrod away from the block deck-avoiding a previously mentioned pitfall of using original Boss 429 heads on a standard block. Another benefit of the revised pushrod angle is reduced side load on the lifter bore, a real advantage if running a solid roller cam with lots of spring pressure.

Photo Gallery

View Photo Gallery

Kaase Intake Manifold
The new Boss Nine intake manifold is a single-plane unit that stands just 1 1/4 inches taller than stock, and can be used on either Kaase or original heads. Available with either a 4150 or Dominator flange, dyno testing has found this intake to be worth big power over either a period NASCAR spider intake, or the stock dual plane. Unbelievably, on a stout 466-inch mule, the Kaase intake was worth about 50 hp more than the NASCAR piece and 100 horses more than the stocker.

Wouldn't You Like To See A Race Between These "Super Bosses"?
Having retired from a successful drag racing career in the mid-1960s, Al "The Lawman" Eckstrand was on a more benevolent endeavor when he linked up with Ford to bring driving safety demonstrations to thousands of Vietnam-era servicemen. Touring the Pacific Rim with several "lesser" Mustangs, the eye candy of the tour was clearly this outrageous supercharged '70 Boss 429. Years later, former servicemen can still recount seeing the blown Boss in theater, even fired up on the flight deck of U.S. Navy aircraft carriers. The last we knew, the Lawman "Super Boss" was owned by pro wrestler Bill Goldberg.

Bob Tasca's influence on '60s performance Fords is well known, as is one of Tasca's most famous cars of the era, the '69 Tasca "Super Boss." Reputed to be the seventh Boss 429 built, KK1214 was promptly modified for promotional use with a Larry Shinoda-designed paintjob, and an all-aluminum 494-cube Can-Am motor. Touring a wide variety of dragstrips around the country, it is said that Tasca would offer $1,000 to anyone capable of beating it in the 1,320. We imagine the complete story was that challengers had to likewise be street cars running through the muffs, and on street tires. In such trim, the Super Boss ran 11-second e.t.'s, so we're apt to think Tasca didn't lose much money in the endeavor-but certainly gained notoriety for himself, Ford, and the Boss 429. The Tasca "Super Boss" currently resides in Brent Hajek's collection.