How Shelby Works

The 1964 Shelby AC Cobra was one of Carroll Shelby’s first American masterpieces.

When heart trouble forced Carroll Shelby to retire from driving race cars after he won the LeMans 24 Hours in 1959, the one-time Texas chicken rancher turned to building stark, incredibly fast road cars to suit himself and other like-minded enthusiasts. The first were the legendary Shelby-Cobras.

Starting with lithe, lightweight Ace roadsters from A.C. Cars in England, Carroll replaced a plodding small six-cylinder engine with potent Ford V-8s: initially 260- and 289-cubic-inch engines with up to 306 horsepower, then mammoth 427s making up to 425 bhp. The result was a hairy thrill on the road and nearly unbeatable in major-league sports-car racing.



Even the "little" 289 could scale 0-60 mph in 5.5 seconds and exceed 135 mph. The otherworldly 427s needed just 4.2 seconds 0-60 on the way to 165 mph.

Shelby built 654 small-block Cobras and some 350 big-block versions from 1962 to '68. All have since become prized collector's items fetching six-figure prices (sometimes more), thanks to a fabled competition record (seven U.S. national road-racing championships, the World Manufacturer's title in 1965) and a raw, elemental nature unmatched by other sports cars.

Those same factors explain the numerous Cobra "replicars" that appeared after them and which Shelby fiercely fought against. Shelby also contributed to the mid-engine GT40 and Mark IV prototypes that took Ford to the racing pinnacle by winning the 24 Hours of LeMans in 1966-69.

Equally famous, but more popular and practical, was the series of limited-edition Shelby Mustang GTs built in 1965-69. The first, named GT 350 for no particular reason, was a race-inspired conversion of Ford's new 1965-66 "ponycar" carried out by the small Shelby American shop in Los Angeles. Early Shelby Mustangs were uncompromising grand tourers equally at home on the track. Post-1967 models were planned and built by Ford and were thus "softer," though still plenty exciting.

Ford Division chief Lee Iacocca had asked Shelby to modify the Mustang so it could win the Sports Car Club of America's national B-production championship. The GT 350 did just that in 1965-67, virtually running away from the field to give showroom Mustangs a "competition-proved" aura.

The 1965-66 GT 350 began as a white, blue-striped Mustang fastback supplied with the excellent small-block 289 in 271-bhp "Hi-Performance" guise. "Hi-rise" manifold, bigger four-barrel carburetor, free-flow exhaust, and other Shelby changes lifted output to 306 bhp at 6000 rpm. Carroll also specified the Mustang's optional Borg-Warner T-10 four-speed gearbox, plus a stronger rear axle from the full-size Ford Galaxie to replace the stock Mustang's Falcon unit.

Other component swaps included Koni adjustable shocks, Shelby-cast 15-inch alloy wheels wearing high-performance Goodyear tires, metallic friction surfaces for both rear-drum and front-disc brakes, and fast-ratio steering (with relocated front suspension mounting points). A hefty steel tube linked the tops of the front shock towers to reduce body flex in hard cornering.

The result of all this was near-neutral handling instead of the stock Mustang's strong understeer, plus 0-60 mph acceleration of just 6.8 seconds -- impressive even today -- and over 120 mph all-out. An optional Paxton supercharger, offered during 1966, boosted horsepower beyond 400 and cut the 0-60 time to just five seconds. Shelby built only such 11 cars, though a handful of stock GT 350s received owner-installed "blower" kits.

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The 1969 Ford Shelby GT 500 advertised its horsepower at 335 to calm insurance companies, but its actual output was close to 400 hp.

As planned, Carroll Shelby also developed a race-ready GT 350R with the same engine as competition Cobra 289s. That meant a nominal 350 bhp -- an outstanding 1.21 bhp per cubic inch. To minimize weight, the gearbox got an aluminum case and the interior was stripped down to a single racing seat with safety harness, plus protective roll bar.

Competition tires and super-duty suspension were specified, too. The front bumper was replaced by a fiberglass air dam with a large central slot for feeding in extra air. A few GT 350Rs were built with all-disc brakes, 400-bhp 289s, and wide tires under flared fenders.



As if all that weren't enough, Shelby devised a special GT 350H for Hertz Rent-A-Car, which ordered 936 examples. All carried Ford's three-speed Select-Shift Cruise-O-Matic transmission and black paint set off by gold stripes. Hertz rented them for $17 a day and 17 cents a mile. Some customers violated their contracts by racing the cars, but probably not as many as once thought. In any case, Hertz lost money on the venture and bailed out after one year.

In all, Shelby built 562 GT 350s for '65 and another 2378 to '66 specs, including R-model racers and Hertz cars, plus six prototype '66 convertibles. That was good production for such a specialized machine, but profit-minded Ford wanted far more. As a result, the original Shelby concept began to be watered down.

Ford bowed a heavier, restyled ponycar for 1967 with a first-time 390-cid V-8 big-block option. Typical of the man, Carroll went one better by offering Dearborn's new 428-cid V-8 for a second Shelby Mustang, the GT 500. Horsepower was conservatively advertised at 335, mainly so insurance companies wouldn't worry, but was closer to 400 actual.

The GT 350 returned with its previous power rating, but the true figure was now under 300 because the original steel-tube headers were eliminated to satisfy noise regulations. Both Shelbys sported a longer, more-aggressive new fiberglass nose, crisply clipped "Kamm" tail with prominent spoiler, and other appearance departures from regular Mustangs, plus small chassis refinements.

Interiors gained a large black-finish roll bar with built-in inertia-reel seatbelts. Shelby built 3225 of his '67 GTs, which sold for around $4000, down some $500 from the 1965-66 cars that were themselves incredible high-performance buys.

The 350 and 500 returned for '68 in convertible as well as fastback form, but all were somewhat less special than the '67s. Interiors, for instance, were stock Mustang save a console-mounted ammeter and oil-pressure gauge, and there were cushy new options like air conditioning, power steering, and automatic transmission. Styling was modified via a wider hood scoop and wide taillights with sequential turn signals (lifted from the Mercury Cougar).

The new convertibles listed about $100 above comparable fastbacks. At midseason, the GT 500 became the GT 500KR -- "King of the Road" -- denoting Ford's latest 428 "Cobra Jet" engine with jumbo ports and a new intake manifold fed by a huge four-barrel Holley carb. Fast¬backs rose to $4117 for the 350, $4317 for the 500, and $4473 for the KR. The costliest '68 Shelby was the KR ragtop, at $4594.

With Ford now calling the shots, the '69 Shelbys became even more like that year's fully redesigned stock Mustangs. Styling remained distinctive but was busier, with a big loop bumper/grille, scoops and ducts most everywhere, and reflective tape stripes midway up the flanks. GT 350s were demoted to Ford's new 351 "Cleveland" V-8 with 290 bhp; GT 500s, no longer KRs, stayed with the Cobra Jet, still at a nominal 335 bhp.

But after just 3150 of the '69s, plus 636 leftovers sold as 1970 models, Shelby and Iacocca agreed to end the Mustang GT program in the face of blossoming government regulations, spiraling insurance rates (the cars' accident record was staggering), and sales interference from hot new production Mustangs like the Mach I and Boss 302. Like the Cobras, however, these Shelbys quickly became high-priced, highly sought after collector cars.

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The 1987 Dodge Shelby Charger GLH-S stood for “Goes Like Hell -- Some more,” an upgrade over the original GLH model.

The Mustang experience had soured Shelby on being an auto manufacturer, so he turned to tending his other businesses. Iacocca, meantime, was promoted to Ford Motor Company president in 1970. He continued as such until the summer of '78, when he was abruptly fired by chairman Henry Ford II in a celebrated row that was as personal as it was public. (HFII was reportedly jealous of Iacocca's growing prominence and power in Dearborn). Later that year, Iacocca made his equally celebrated move to the presidency of then-moribund Chrysler Corporation, where he was named board chairman in 1979.

After helping pull Chrysler from the financial brink, Iacocca called on old friend Shelby to add some needed pizzazz to the corporate lineup -- timely, as performance was starting to make a comeback throughout Detroit. Carroll agreed, and Chrysler duly announced his arrival in 1982 as a "performance consultant" who promised to "bring excitement back to the auto industry."



The first fruit of the renewed Shelby/Iacocca partnership was the Chrysler Shelby California Development Center. Set up in Santa Fe Springs, near Los Angeles, CSCDC was assigned to work with Chrysler engineers in exploring new technology for future models and to devise specific performance packages for Chrysler's "excitement" division, Dodge.

Two immediate results were the 1983-86 Shelby Charger coupe and Omni GLH ("Goes Like Hell") hatchback, essentially "Shelbyized" versions of those workaday front-drive subcompacts. Both offered extra power, tight suspensions, distinctive styling touches, and attractively low prices. Things went a step further in February 1986, when Shelby and Chrysler Motors chairman Gerald Greenwald announced the formation of Shelby Auto¬mobiles, Inc. (SAI) in nearby Whittier, California, to build high-performance Dodge-based limited editions.

With that, March 1, 1986, introduced the first Shelby-marque car since the final Mustang GTs: a quicker, more-powerful GLH called GLH-S ("Goes Like Hell -- Some more"). It had a 2.2-liter (135 cid) turbocharged Chrysler four-cylinder engine that Shelby tweaked to 175 bhp via an air-to-air intercooler, equal-length intake runners, and other alterations. Helped by a mandatory five-speed manual transmission, the GLH-S offered brisk eight-second 0-60 mph performance -- and truly horrendous front-drive torque-steer.

In February 1987, SAI began building a Shelby Lancer based on Dodge's recently launched "H-body" four-door hatchback sedan. Base-priced at $16,995, it also came with a five-speed and the 175-bhp turbo-four, but offered a tamer 146-bhp turbo 2.2 with TorqueFlite automatic for $1000 extra.

The Shelby Lancer took Carroll into a new realm: the high-style European-type sports sedan. Equipment was suitably lavish, with power everything, all-disc brakes (instead of rear drums), and a special Shelby Touring Suspension (good for 0.80g on the skidpad). Handling was sharp and manual-shift acceleration lively -- 7.7 seconds 0-60 mph in most published road tests -- but shift action was clunky, the ride jarring, turbo "lag" annoying, and quietness conspicuously absent.

As ever, though, Shelby wasn't building cars for the masses. After completing 800 Shelby Lancers by July of '87, SAI turned to a similarly modified Dodge Shadow compact called the Shelby CSX. Offered only as a two-door hatchback sedan, it weighed 200 pounds less than the midsize Shelby Lancer and was thus a bit quicker. The factory claimed 0-60 in 7.1 seconds and a standing quarter-mile of 15.1 seconds at 90 mph. Most road tests agreed.

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Carroll Shelby wrote two postscripts to his Ford experience. The first involved a dozen GT 350 convertibles built from restored Mustangs, essentially brand-new '66 models identical to Shelby's original six prototypes. All sold quickly despite stiff $40,000 price tags. Shelby sprang a similar surprise in early '93 by announcing that four dozen "continuation" Cobra 427SCs would be assembled from never-used stock parts he had stored away back in the '60s.

A heart transplant forced Shelby to slow down for a while, yet he somehow found the time and energy to be the "spiritual conscience" behind the Cobra-like 1992 Dodge Viper RT/10. In late 1997 he lent his name to something rather unusual for him: a hot-rodded Dodge Durango sport-utility vehicle.



Premiered as a concept at the SEMA aftermarket-industry show, the Shelby SP360 was a limited-edition SUV created by several independent tuners hoping to win Carroll's endorsement, which they did. The concept used a supercharged 5.9-liter (360-cid) Dodge V-8 making 360 bhp, plus a fortified suspension and other Shelby-style features, including Cobra Blue paint and broad white dorsal striping. Dodge said only 3000 SP360s would be built, all in 1999, but actual production was minuscule.

By this point, however, Shelby had long since drifted away from Chrysler (his pal Iacocca had left in 1992) and was pursuing various businesses new and old, plus charitable projects. After moving some of his enterprises to new facilities near the recently opened Las Vegas Motor Speedway, he began advertising another "new-old" Cobra, the CSX 4000. This looked much like an original 427, but was sold without an engine as a "component vehicle," again to sidestep pesky "gummint" rules.

Shelby was now in his 70s, but as restless as ever. "I'm tired of imitations," he had told the press. "Folks have put the Cobra name on all sorts of stuff...but none of them were Shelby Cobras. Before they throw the last shovel of dirt on me, I want to take one last shot at an honest-to-goodness Cobra."

Though not exactly a Cobra, the prosaically named Series I (internally designated CSX 5000) would prove the most-vexing car of Shelby's storied career. It entered production -- with great difficulty -- in 1999 after some five years of second thoughts and false starts. The original plan, revealed in April 1994, was for a twin-turbo V-8 roadster with 500 bhp, a chassis made of high-tech carbon fiber, and a staggering $200,000 price tag. Only 500 would be built.

The engine would come from none other than flagging Oldsmobile. Olds general manager John Rock, a cowboy type worthy of Shelby himself, suggested the new 4.0-liter twincam Aurora V-8, hoping an Olds-powered "Cobra for the '90s" would do for his brand what the Viper had done for Dodge. But market realities soon forced downshifting to a less-ambitious $50,000 machine.

The Series I premiered as a "pushmobile" at the Greater Los Angeles Auto Show in January 1997. A running prototype was tested the following October, by which time the chassis was a steel-tube structure supporting a carbon-fiber body. Initial deliveries were planned for 1998. But uncharacteristically, Shelby American underestimated production costs by a whopping $60,000 a car.

That, plus unforeseen development glitches and construction delays with the new Las Vegas plant, pushed production back to mid-1999. By that point the price had soared to near $100,000 and soon went to nearly $114-grand. Despite sizable deposits from 300 would-be owners and a handful of Olds dealers who would sell the car, the project was almost bankrupt by year's end, when only 20 Series Is had been built.

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The 1999 Shelby Series I sold for as much as $175,000, with only 249 cars of a planned 500 produced.

Just when all seemed lost for Shelby, Venture Industries, which supplied the carbon-fiber bodies, rode to the rescue, offering some $10 million for a 60-percent stake in Shelby American. By late April, Shelby American was honoring original contracts with dealers, depositers, and suppliers; lingering engineering bugs were fast being squashed; and production was up to 1.2 cars a day, thanks to more-efficient methods. But about 250 Series Is were still unsold, and price had to be hiked again -- first to $160,000, then to near $175,000 -- close, ironically, to the original 1994 figure.

For the few who got to drive it, the Series I was a genuine Shelby with all the thrills that name implied. Riding a tight 96.2-wheelbase, it was three inches wider than a C5 Corvette yet scaled a feathery 2650 pounds. The carbon-fiber body weighed only 130 pounds, yet was stronger than steel.



So, too, the chassis, made up from extruded-aluminum members and boasting a resonance frequency of 52 hertz, more than double the best then attained in production cars. Suspension was also mostly aluminum, with four-wheel independent geometry by upper and lower control arms, adjustable shocks, and coil springs attached to Formula 1-style pushrod-operated inboard rocker arms. This layout not only reduced undesirable unsprung weight, but could be easily custom-tuned.

An antiroll bar lived at each end. Brakes were contemporary Corvette discs of 13-inch diameter fore, 12 inches aft. As with the Viper, though, Shelby felt no need for antilock control. Steering was the expected power rack-and-pinion. Rolling stock comprised five-spoke 18-inch alloys wearing Z-rated Goodyear Eagle F1 Supercar tires sized at P265/40 front, P315/40 rear.

A Corvette six-speed manual gearbox was sited in the tail, helping achieve the ideal 50/50 weight distribution. The Aurora V-8 got new camshafts, intake manifold, exhaust system, and control chip, modest changes that nevertheless yielded 320 bhp -- up 70 from stock -- and 30 extra pound-feet of torque (290 in all).

With a stump-pulling 4.22:1 rear axle and carrying just 8.3 pounds per horsepower, the Series I was claimed to do 0-60 mph in 4.4 seconds, 0-100 in 11 flat, and a 12.8-second standing quarter-mile at 109.9 mph. AutoWeek found those numbers credible, though it couldn't confirm them in testing two prototypes.

But the magazine did find the Series I "a blast to drive. It handles like a world-class sports car." Yet this Shelby was no raw-edged Cobra, equipped with standard air conditioning, power windows, leather-trimmed cockpit, and a booming stereo. Some GM bits were obvious inside, but the manual folding top was snug and easy to operate, and workmanship improved to first-class once Venture came aboard. By February 2002, Shelby American had delivered 240 Series Is, with orders for 25 more.

But when a new round of federal regulations required the car to be recertified for sale after 1999, Shelby halted Series I production after 249 units. That seemed to leave the remaining 251 scheduled cars in limbo, but Shelby later marketed them as "component vehicles," like his latter-day Cobras, after securing an outside company to install Olds V-8s postpurchase.

And in line with original plans, that engine was finally available in a supercharged version, making the Series I an "honest 3.3-second [0-60] car," according to Shelby. "There's a lot of people that want them as kit cars," he said in August 2004. "We have had 15 or 20 bites and we've [already] sold two or three." The rest will doubtless find homes, too.

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The 2006 Ford Shelby Mustang CS 6 was sold as a "package" of components
The 2006 Ford Shelby Mustang CS 6 was sold as a "package" of components
that all added up to an incredible machine.

Shelby was also far from finished with the Cobra. Indeed, it remained the heart and soul of his business. Though "component vehicles" are beyond the scope of this article, these merit mention as lineal descendants commonly accepted as true Shelby Cobras. Not "originals," however. Again typical of the man, Ol' Shel couldn't resist updating his signature car with new technology, components, and materials. Anything to go faster.

There were several variations, each carefully built in small numbers, some bodied in fiberglass instead of aluminum. Announced in 2002 were specially trimmed 40th anniversary Cobras, a 40-unit run split between a small-block CSX 8000 and the first 427 model with an aluminum-block supercharged engine. Appearing two years later were an AC 427 S/C (CSX 1000) and AC 289 FIA (CSX 7500). The initials signified bodies supplied by AC Motor Holdings, the Malta-based descendant of Britain's A.C. Cars, which had sold various Cobras of its own through several corporate incarnations.



Now Shelby and AC had finally joined forces (after settling an intellectual property dispute), which seemed only right. By the mid-2000s, the Cobra duo had become a trio comprising big-block 427 (still CSX 4000), 289 Street (CSX 8000), and track-ready 289 FIA (CSX 7000). All these "continuations" were sold as rolling chassis ready for installation of Shelby-vetted "crate motors" based on period-correct 1960s Ford engines. Of course, Shelby sold those too, plus all manner of parts and accessories.

There was also another "continuation" Shelby Mustang, the GT 500E "Eleanor," star of the auto-heist film Gone in 60 Seconds. Built in Texas, again from pristine restorations, the Eleanors carried a Shelby-tuned 5.4-liter Ford V-8 and carefully updated styling. Only a handful were completed, all in 2003.

Meanwhile, Shelby renewed personal ties with Ford, lending his priceless first-hand experience to the development of the roadgoing midengine Ford GT patterned on the great, late-'60s LeMans-winning racer. For Shelby, still energetic at 80, it must have been an emotional homecoming.

He then served as "spiritual advisor" on Ford's 2004 Cobra concept roadster (a mix of GT components and a mighty new 605-bhp front-mounted V-10) and a rebodied 2005 follow-up, the rakish Shelby GR-1 coupe. More significant to this article were his contributions to showroom models, starting with the muscular 2007 Shelby-Cobra GT 500 based on Ford's newly redesigned Mustang.

As ever, though, Shelby couldn't let Ford have all the glory. Bringing history full circle, he teamed with Hertz on a modern "rent-a-racer," the Shelby GT-H. Available at select U.S. airports starting in mid-2006, it began, fittingly, as a Mustang fastback, a V-8 GT with automatic transmission (now a five-speed unit).

Shelby shopped Ford Racing Performance Parts for a "cold-air kit," low-restriction "cat back" exhaust system, and a new engine-control chip to realize 325 bhp and 330 pound-feet of torque, up 25 bhp and 10 pound-feet from stock. The same source also supplied special high-rate shocks, low-rise springs, heftier antiroll bars, and a front strut-tower brace, plus a tighter rear-axle ratio. Livery was predictably retro: prominent gold stripes, black paint, thin-bar grille, and racing-style lock pins on a domed Shelby-designed hood, plus a modest rear spoiler and subtle aerodynamic fairings beneath the nose and rocker panels.

With all this, the GT-H promised much excitement at Hertz service counters. Disappointment would be inevitable, too, as only 500 cars would be built for rental at 14 far-flung points. The clamor should be no less fierce once GT-Hs reach the collector market, as they inevitably will.

For those who'd rather buy than rent, Shelby had another 2006 surprise, the CS 6 package. This picked up on an idea Ford had toyed with back in the 1960s: a high-performance six-cylinder Mustang. In yet another link to the past, Shelby offered a Paxton supercharger (a Novi-1200 centrifigal unit) for the base-Mustang 4.0-liter V-6.

When properly installed (by the customer or a shop of his or her choice), horsepower jumped by at least 140 to a stout 350. Also available were a suitably uprated suspension, brakes, custom 20-inch American Racing wheels, exhaust, and body addenda (including hood, front fascia, side scoops, and grille) a la GT-H. Shelby sold the CS 6 components separately or as a complete package for $14,999.

A signal event in the business story came in 2004 with the formation of Carroll Shelby International, Inc. as a public stock company. CSBI, to use its ticker symbol, oversees Shelby Automobiles in Las Vegas, which not only builds vehicles but offers consultant services in design, engineering, and prototype construction. The CSI umbrella also covers Los Angeles-based Carroll Shelby Licensing, Inc., established in 1988 as basically a legal clearinghouse for Shelby vehicle designs, trademarks, and other intellectual property.

That's the Shelby saga so far, but it's surely far from finished. Carroll Shelby has been described as having "the unique ability to combine elements so that their sum becomes greater than the total of their parts." Though the same can be said for other automotive geniuses, there's never been one like ol' Shel -- and never will be again.

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