Shelby Sports Cars


The Shelby Cobra 427 was on of the most powerful and formidable sports cars every made. See more pictures of Shelby cars.

The story of Shelby sports cars is very much the story of Carroll Shelby, the colorful Texan inextricably linked by name and temperament to some of the greatest high-performance machines of all time.

As you’ll learn in this article, Shelby was a successful race driver who turned automotive entrepreneur when a heart condition curtailed his time behind the wheel. In September 1961, Shelby learned that England’s AC cars was losing the engine supplier for its open two-seater and seized an opportunity.

Shelby talked AC into providing him cars, then convinced Ford to supply its new small-block V-8. The first result, the AC Shelby Cobra of 1962, was a sensation. It combined the spot-on proportions and clean lines of a classic British roadster with the stout heart and one-horsepower-per-cubic-inch punch of a 260-cube American V-8. This car soon gave way to the 289-cubic-inch power behemoth known as the AC Shelby Cobra 427.

Shelby Cobra 260/289 and AC 289

Cobras are often customized in some way. Note this example’s non-stock roll bar and chrome wire wheels.
Cobras are often customized in some way. Note this example’s non-stock roll bar and chrome wire wheels.

Though the Shelby Cobra’s conception, development, and production history are well known, there’s still a little controversy over the name and the way the cars were built. But there’s no disputing its originator: American Carroll Shelby, the former Ferrari race driver and occasional chicken farmer.

Shelby conceived the idea of shoehorning Ford’s forthcoming new small-block V-8 into the light and lively AC Ace in 1961. The first car was completed in February 1962, and deliveries to American customers began later that same year. This and subsequent Cobra models would be built over just a five-year period, but they were among the most charismatic and fearsome roadgoing sports cars ever produced. The British liked to call them AC Cobras, while Americans preferred Shelby-AC Cobra or plain Shelby-Cobra. Today, they’re remembered mainly -- and vividly -- as Cobra.

 

That first Shelby Cobra’s basic chassis, suspension, and body design differed little from that of the Ace and Ace-Bristol roadsters that the British firm had been building for some years. As luck would have it, Shelby approached AC about supplying engineless Aces just as Bristol engine supplies began to decline and AC was trying to decide what to do next.

By the time Ace development, such as it was, had been completed, the chassis had been stiffened up a little (much of it shared with late-model Acecas) and a Salisbury final drive (Jaguar E-Type/Mk X type) complete with limited-slip differential had been installed. Cobra styling was almost exactly the same as that of the latter-day Ace, with the final, smaller grille but flared wheelarches to accommodate wider tires.

All Shelby Cobras had four-wheel disc brakes. Inboard rear brakes were contemplated, but production cars had outboard units. The steering box was canted over to clear the Ford engine, but steering and suspension geometry changes were minimal otherwise. Assembly took place in the UK except for engines and gearboxes, which were installed once the cars arrived at Shelby’s small assembly operation in Venice, California.

The engine, of course, was the lightweight, compact thinwall V-8 from Ford’s new 1962 Fairlane intermediate, initially sized at 260 cubic inches and fitted to the first 75 Shelby Cobras built. Mated to it was a 4-speed Borg-Warner all-synchromesh manual transmission. The next 51 cars were equipped with the 289-cid small-block enlargement. Then, as later, the AC chassis really wasn’t rigid enough to handle the engine’s torque, so not all of the Cobra’s wheels stayed on the ground at all times. But this only made an already exciting car even more of a challenge to drive well.

Carroll Shelby imported the dashboard from the AC Ace pretty much intact for the original Cobras.

The next Shelby Cobras, called “Mark II” by AC designers, were built from the beginning of 1963. They retained the original transverse-leaf-spring Ace chassis and the 289 engine but featured rack-and-pinion steering, a definite improvement. Exactly 528 cars were built before the old Ace chassis was discontinued.

Although the original plan called for the Shelby Cobra to be sold only in the U.S., it didn’t last long. The first right-hand-drive cars were completed as early as summer 1963, though it wasn’t until the end of 1964 that AC officially launched the 289 model on the British market. The cars were also sold in Europe.

The original Ace-chassis Cobra ended in early 1965, when production changed over to the truly ferocious Cobra 427, built on a new chassis dubbed “Mark III.” But the small-block Cobra lived on in Europe as a 289 version of the new platform called AC 289. Just 27 were built before all Cobra production ceased in December 1968.

To learn more about Shelby and other sports cars, see:

To learn more about Shelby and other sports cars, see:

Shelby Cobra 427

The Shelby Cobra 427's low stance, bulging stern, and hulking tires give this big-block Cobras a menacing appearance.
The Shelby Cobra 427's low stance, bulging stern, and hulking tires give this big-block Cobras a menacing appearance.

The AC/Shelby-Cobra had been designed so quickly that most of its chassis, suspension, and general structure was a virtual carryover from the last of the British six-cylinder Aces. After only three years, therefore, a much more purpose-built Shelby Cobra, the Mark III, was introduced.

Although the two Mark III models -- 289 and 427 -- looked basically alike, they differed in almost every other respect. The most obvious one was the engine of the new 427 model, named for the cubic-inch displacement of its big-block Ford V-8. In addition, it sported a new chassis, new suspension system, and important changes to the bodyshell. With this brutish engine, the Cobra Mark III was sold only in the U.S. Its European cousin, the AC 289, retained the small-block V-8 of the earlier Mark II Cobra (see Shelby Cobra 260/289 abd AC 289).

Both Mark IIIs continued with the basic ladder-style tubular chassis inherited from the AC Ace, though with larger-diameter tubes spaced further apart. Coil springs replaced the old transverse leaf springs front and rear, still acting on classic, independent double wishbones.

Shelby and Ford publicity at the time suggested that this suspension had been computer-generated, but the more prosaic truth is that it was conventionally designed by Bob Negstadt of Shelby-America and Alan Turner of AC. Regardless, the result was more favorable geometry for sharper steering, plus handling that was about as good as this Fifties-vintage chassis could deliver.

With racing in mind -- and following the old American axiom that “there’s no substitute for cubic inches” -- Shelby’s team pursued maximum power by stuffing in the largest V-8 they could. Thus, the small-block 289 V-8 gave way to the massive 427-cid Ford “semi-hemi,” a close relative of the engine used in Ford’s NASCAR racers and modified for the GT40 Mark II and Le Mans-winning Mark IV World Manufacturers Championship cars.

But wait. Although the ultimate Cobra was always known as the “427,” it seems that many of them were actually built with the low-stress low-output 428 engine. So what difference does a cubic inch make? Plenty, for these engines had completely different cylinder dimensions (427 bore/stroke = 4.24 × 3.78 in., 428 = 4.14 × 3.98 in.) and cylinder head castings. In short, the 427 was a racing engine, while the 428 was designed for the big Galaxie and Thunderbird passenger cars -- considerably heavier than the 427 and by no means as “tuneable.”

Though titled the Shelby Cobra 427, these cars were actually built with a 428 engine.

The Cobra 427 body was similar to that of the Mark III AC 289 and included many common sections. However, wider track dimensions and much fatter tires made it necessary to flare the wheelarches considerably, swelling overall width by seven inches compared to the Mark II shell. This and the burly engine made the 427 a muscular monster that looked as aggressive as it sounded and was only slightly slower than an Atlas rocket.

In fact, the 427’s performance was little short of staggering. Even “customer” cars had 390 bhp, while race tuning could provide up to 480 bhp and a pavement-peeling 480 lbs-ft of torque. For its three years of production, the Cobra 427 was undoubtedly the wildest and most exciting machine on American roads. Come to that, it still is.

Alas, sales ran down, so production did too, in 1967. For 1968, the Cobra name (which now belonged to Ford, not Carroll Shelby) began to appear on hopped-up Mustang engines.

In truth, any Cobra, but especially the 427, was too fast for its chassis, and not nearly as refined -- or as reliable -- as it should have been. Yet because of their rarity and shattering performance, Shelby’s high-performance hybrids continued to grow in stature and collectibility as the years passed. Demand quickly outstripped supply, resulting in a slew of Cobra replicas in the Seventies and especially the Eighties. Most employed different and -- believe it or not -- even cruder chassis designs.

Fortunately, the small but persistent demand for real Cobra motoring prompted Brian Angliss and his UK-based Autokraft company to build “Mark IV” Cobras using surviving original tooling purchased from AC, which Autokraft has since acquired. These cars now have Ford’s official sanction, which only goes to show that some legends simply will not be consigned to history.

To learn more about Shelby and other sports cars, see:

To learn more about Shelby and other sports cars, see:

Shelby GT-350

A sports car in ponycar clothing, the Shelby GT-350 was a race winner and an American classic.
A sports car in ponycar clothing, the Shelby GT-350 was a race winner and an American classic.

Real sports cars are not gilded versions of passenger coupes, but sometimes, sports cars are as sports cars do. So it goes with the Shelby GT-350.

When Carroll Shelby reworked a 1965 Ford Mustang to within an inch of its ponycar life, the result was a howling, hard-riding, two-seat fastback that beat the pants off a passel of “authentic” sports cars. “It is...certainly the most sporting street machine we have driven in a long while, and anyone who tells you it isn’t a genuine sports car is nuts,” said Car and Driver in its very first test of the Shelby GT-350.

With Mustang a sales sensation after its April 1964 debut, Ford chief Lee Iacocca sought some performance credibility by going Corvette-hunting in Sports Car Club of America B-production racing. He recruited Shelby, who had just stuffed the British A.C. Ace with Ford power to create the Cobra.

A wood-rimmed wheel, extra gauge pod, wide seat belts, and side-exit exhausts were standard on the Shelby GT-350.

Shelby’s team worked out of a small shop in Venice, California. Ford shipped over white fastback Mustangs fitted with the “Hi-Performance” 289 V-8, four-speed gearbox, front discs, and Ford Galaxie drum brakes and rear axle in place of the stock Mustang’s lighter Falcon pieces. Shelby-American stiffened the structure, supplemented the suspension, reworked the steering, and fitted 15 x 6-inch wheels with Goodyear Blue Dot highspeed tires. It added 35 hp with an aluminum manifold and larger carb, slapped on side-exit dual exhausts, and installed a 4.11:1 locking differential. All cars got a scooped fiberglass hood, and most had extra-cost blue racing stripes. By omitting the rear seat, Shelby GT-350s could race as sports cars rather than sedans. Competition “R” models had no interior trim and got a blueprinted Cobra racing 289, fiberglass nose valance with cooling ducts, plexiglas side windows, 34-gallon gas tank, and 15 x 7 magnesium wheels.

The Ford V-8 gave the Shelby GT-350 well over 300 horsepower depending on the specific model.

Priced at $4547 -- $1000 below a Corvette -- the Shelby GT-350 got rave reviews, while the $5950 R-model cleaned up in B-production, winning the 1965 national championship and four of five regional titles. The same cars won again in ’66 and in ’67.

The 1966 Shelby GT-350s got plexiglas rear quarter windows, bodyside air scoops, and eventually came in more colors. They had a backseat, tamer suspension and steering, and offered the locking diff as an option -- along with automatic transmission. Shelby even built about 1000 gold-striped GT-350H models for the Hertz rental fleet. Shelby Mustangs grew increasingly softer after ’66, and were eventually absorbed into regular Ford production, leaving the original editions as exemplary exceptions to the sports-car rule.

To learn more about Shelby and other sports cars, see:

Shelby GT-350/GT-500/GT-500KR

The Shelby GT-500 KR (standing for "King of the Road") was a souped-up redesign of the original GT-500.
The Shelby GT-500 KR (standing for "King of the Road") was a souped-up redesign of the original GT-500.

Mustang put on pounds and inches for ’67, so the Shelby GT-350 did too. But that wasn’t the half of it. Ford now offered its big-block 390 V-8 as the top Mustang performance option. Typical of the man, Carroll specified the physically identical 428 engine for a second Shelby called GT-500. It was a popular move, the newcomer outselling its smaller-capacity stablemate two-to-one.

Still, performance began taking a back seat to styling and luxury with the ’67s, because that’s where the money was spent. Ford was still spending it, of course, but was now more intimately involved with the Shelbys -- and more determined that they turn a profit.

Because Mustang was heavier for ’67, and with customers wanting a more manageable Shelby, power steering and brakes became mandatory Shelby options. Mustang’s newly reworked ’67 interior was little altered for the Shelbys, though they continued with several unique touches: distinctive racing steering wheel, additional gauges, and a genuine roll-over bar with built-in inertia-reel shoulder harnesses. Comfort and convenience options proliferated: air conditioning, tinted glass, tilt steering wheel, and more.

The interior of the later Shelby GT-350s and GT-500s maintained Shelby's standard of simple, powerful design.

Outside, Ford’s Chuck McHose and Shelby-American’s Pete Brock styled a new fiberglass nose to match Mustang’s longer ’67 hood, with a “big-mouth” grille bearing twin center-mount high-beam driving lamps (since moved outboard on some cars to comply with headlight-spacing regulations). Scoops were everywhere -- hood, lower bodysides, sail panels -- all functional and, of course, larger. Out back, a special trunklid with integral spoiler appeared above wide taillamp clusters purloined from the new Mercury Cougar.

All these touches plus Mustang’s new full-fastback styling made the ’67 Shelbys handsome, fast-looking cars. Alas, Shelby GT-350 performance sagged under the weight of all the new fluff. Its horsepower was ostensibly the same as before but surely less in actuality, as the steel-tube exhaust headers had disappeared.The new GT-500 was quick, but curiously disappointing. Carmakers began using more conservative horsepower ratings for ’67 as a sop to insurance companies. The Shelby’s 428 had an advertised 335, though again it was probably more. Car and Driver, whose test car took 6.5 seconds 0-60 mph, said that while the 428 “isn’t the Le Mans winner,” the GT-500 “does with ease what the old [GT-350] took brute force to accomplish.” But Road & Track, which recorded 7.2 seconds for the same sprint, said the Shelby GT-500 “simply doesn’t have anything sensational to offer . . . . A [standard] Mustang with the 390 cu. in. engine option does as well.” As ever, Shelby had an answer: an optional 427 -- which was the Le Mans engine -- rated at 390 bhp. Still, not many were ordered.

The Ford big-block V-8, the hallmark of the Shelby GT series, gives the GT-500KR enough muscle to run with the big boys.

Dearborn’s control over the Shelby-Mustangs became total for ’68. Production was moved from Los Angeles to Michigan, where stock Mustangs (from Ford’s Metuchen, New Jersey plant) were converted into Shelbys by the A.O. Smith Company under contract. The fastbacks gained convertible companions with built-in roll-over hoop, and all four models sported a full-width hood scoop, new hood louvers, a larger grille with square running lamps (not driving lights), sequential rear turn signals, and minor trim changes.

With federal emissions limits in force, the Shelby GT-350 was switched to Ford’s newly enlarged 302-cid small-block -- and lost a lot of power. However, the Paxton supercharger option returned from ’66 to add about 100 horses, though it, too, found few takers. The Shelby GT-500 initially retained its 428, now at 360 bhp. A few, however, got ordinary 390 V-8s. This probably stemmed from a shortage of 428s due to an engine-plant strike, but buyers weren’t told about the substitution, which was nearly impossible to spot.

Mid-year brought some redress, however, in the Shelby GT-500KR (for “King of the Road”). This had the new Cobra Jet engine, basically the existing 428 with big-port 427 heads, larger intake manifold and exhaust system, and an estimated 40 extra horses. Ford also tossed in wider rear brakes.

Shelby production rose for the fourth straight year in 1968, but would go no higher. The press mostly yawned at the plusher ’68s, and Ford made no effort to race either the ’67 or ’68 Shelbys. Not that they’d have been competitive. They’d grown too big, too soft, too heavy -- not at all the race-bred stormers their predecessors had been. And Ford only managed to dilute their appeal further with Shelbyesque showroom Mustangs like the ’68 GT/CS (“California Special”) notchback. With all this, the Shelby-Mustang wasn’t dead by the end of ’68, but it didn’t have lone to live.

To learn more about Shelby and other sports cars, see:

Shelby GT-350/GT-500

The final run of the Shelby GT-350 and GT-500 line had unique touches in outer styling, but were quite similar to their forefathers inside and under the hood.

There’s little to say about the 1969-70 Shelby GTs, other than that they were even more like production Mustangs than the 1967-68 editions and thus further removed from Carroll Shelby’s original concept. Of course, they’ll always be treasured as the last of a special breed, but that’ll likely be the only reason.

Not that these cars weren’t, er, interesting. Mustang got a much swoopier new bodyshell for ’69, so the Shelbys did too. Both fastback and convertible returned in GT-350 and 500 form, differentiated from the weightier, lengthier, much busier production cars by a three-inch longer hood, reshaped front fenders, and a new nose with a big loop-style bumper/grille (all made of fiberglass to hold down weight), plus a clipped tail still bearing a lip spoiler and Cougar sequential turn signals. Scoops were everywhere -- five NACA ducts on the hood alone -- and wide reflective tape stripes ran midway along the flanks. Said Car and Driver magazine’s Brock Yates: “I personally can’t think of an automobile that makes a statement about performance...any better than [this Shelby].”

But brag is one thing, fact another. And the fact was that stiffening emission controls and the new Mustang’s greater weight made the ’69 Shelbys somewhat tamer. The Shelby GT-500 was no longer labelled “King of the Road” but retained that ’68 model’s 428 Cobra Jet engine, still at a nominal 355 horsepower, though actual output was down 25 horses by most estimates. The Shelby GT-350 was promoted to Ford’s new 351-cubic-inch “Windsor” small-block, with hydraulic-lifter cam, big four-barrel carb, aluminum high-rise manifold, and low-restriction exhaust system. Advertised horsepower was unchanged from that of the previous 302 -- but then, this engine was standard in the new Mach 1 fastback, which cost much less than the Shelby.

Yates derisively described the ’69 Shelby GT-350 as “a garter snake in Cobra skin.” But if the magic was gone -- and it was -- part of the problem was that Ol’ Shel had long ceased to be involved with his cars. In fact, the ’69s were built at Ford’s Southfield, Michigan plant right alongside box-stock Mustangs.

The other part of the problem was new competition from the Mustang line itself. The Mach 1 was interference enough, but mid-year brought the hot Boss 302, a thinly disguised Trans-Am racer for the street, and the incredible Boss 429, a thinly disguised drag racer stuffed full of Ford’s potent “semi-hemi” big-block. Of course, the Bosses were no cheaper or more readily available than the Shelbys, but they were “a curious duplication of effort,” as Yates put it, that only dimmed what luster the Shelbys still had. “The heritage of the GT-350 is performance,” he mused, “and it is difficult to understand why the Ford marketing experts failed to exploit its reputation.”

Perhaps they’d learned Ol’ Shel was tiring of the car business. Ever the individualist, he’d begun by building machines he himself wanted to drive, then watched his Cobras and the original Shelby GT-350 dominate SCCA competition. His efforts with Ford’s assault on the World Manufacturer’s Championship had helped the mid-engine Ford GT racers win Le Mans two years in a row (1966-67) and vanquish Ferraris and Porsches all over the world. But racing was becoming ever-more competitive and costly, and rapidly advancing technology was making it hard for all but a few specialists to apply new engineering principles successfully. By 1970, Shelby had decided that racing wasn’t fun anymore; it was business.

So was building his own cars once Ford muscled in and started calling the shots. And Shelby hated design by committees, where accountants and lawyers often overruled engineers and test drivers. The Bosses and Mach 1 were only last straws.

In a way, time had caught up with both Shelby and his cars. Carroll knew it, and urged Lee Iacocca to end the Shelby-Mustang program after 1970. Iacocca agreed. These final cars were merely leftover ’69s with Boss 302 front spoilers, black hoods, and new serial numbers. At Riverside in October 1969, Shelby announced his retirement as a race-car developer and team manager.

But the last Shelby-Mustangs would not be the last Shelbys. Being who he is, Carroll couldn’t stay away from the car business forever. Today, thanks to his friend Iacocca, he’s working the same kind of magic at Chrysler that he did for Ford, and we enthusiasts are all the better for it.

To learn more about Shelby and other sports cars, see: