Table o contents
History an development
Like mony Breetish specialist manufacturers, AC Caurs haed been uisin the smooth, refined Bristol straight-6 ingine in its sma-volume production, includin its AC Ace 2-seater roadster. This haed a hand-built body wi a steel tube frame, an aluminium body panels that wur made uisin Inglis wheelin machines. The ingine wis a pre-Warld War II design o BMW which bi the 1960s wis considered dated. Bristol decided in 1961 to cease production o its ingine an instead tae uise Chrysler 331 cid (5.4 L) V8 ingines. Although untrue, it is commonly believed that AC wis left wi'oot a future source o pouer an that American ex-racin driver Carroll Shelby saved the company frae bankruptcy. AC startit uisin the 2.6 litre Ford Zephyr ingine in its caurs. In September 1961, Shelby airmailed AC a letter askin them if they woud build him a caur modified tae accept a V8 ingine. AC agreed, providit a suitable ingine coud be foond. He first went tae Chevrolet tae see if they woud provide him wi ingines, but no wantin tae add competition tae the Corvette they said nae. Ford houiver, wantit a caur that coud compete wi the Corvette an they happened tae hae a brand new thin-wall sma-block ingine which coud be uised in this endeavor. It wis Ford's 260 in³ HiPo (4.2 L) ingine - a new lichtweight, thin-wall cast sma-block V8 tuned for hie performance. In Januar 1962 mechanics at AC Caurs in Thames Ditton, Surrey fittit the prototype chassis CSX0001 wi a 221ci Ford V8. Efter testin an modification, the ingine an transmission wur removed an the chassis wis air-freightit tae Shelby in Los Angeles on 2 Februar 1962.. His team fittit it wi an ingine an transmission in less than aicht hours at Dean Moon's shop in Santa Fe Springs, California, an began road-testin.
Production proved tae be easy, since AC haed awready made maist o the modifications needit for the sma'-block V8 when they installed the 2.6 litre Ford Zephyr ingine, includin the extensive rework o the AC Ace's front end. The maist important modification wis the fittin o a stronger rear differential tae handle the increased ingine pouer. A Salisbury 4HU unit wi inboard disk brakes tae reduce unsprung weight wis chosen instead o the auld ENV unit. It wis the same unit uised on the Jaguar E-Type. On the production version, the inboard brakes wur moved ootboard tae reduce cost. The anerlie modification o the front end o the first Cobra frae that o the AC Ace 2.6 wis the steerin box, which haed tae be moved ootward tae clear the wider V8 motor.
The first 75 Cobra Mark I (includin the prototype) wur fittit wi the 260 ingine (4.2 L). The remainin 51 Mark I model wur fittit wi a lairger version o the Windsor Ford ingine, the 289 in³ (4.7 L) V8. In late 1962 Alan Turner, AC's chief engineer completit a major design change o the caur's front end an wis able tae fit it wi rack an pinion steerin while still uisin transverse leaf spring suspension. The new caur entered production in early 1963 an wis designatit Mark II. The steerin rack wis borrowed frae the MGB while the new steerin column cam frae the VW Beetle. Aboot 528 Mark II Cobras wur producit tae the simmer o 1965 (the last US-boond Mark II wis produced in November 1964).
By 1963 the leaf-spring Cobra wis losin its supremacy in racin. Shelby tried fittin a lairger Ford FE ingine o 390 in³. Ken Miles drove an raced the FE-powered Mark II an pronounced the caur wis virtually undrivable, namin it "The Turd." A new chassis wis developed an designatit Mark III.
The new caur wis designed in cooperation wi Ford in Detroit, Michigan. A new chassis wis built uisin 4" main chassis tubes (up frae 3") an coil spring suspension aw aroond. The new caur also haed wide fenders an a lairger radiator openin. It wis pouered bi the "side oiler" Ford 427 ingine (7.0 L) ratit at 425 bhp which providit a top speed o 164 mph (262 km/h) in the standard model an 485 bhp wi a top speed o 185 mph in the competition model. Cobra Mark III production began on 1 Januar 1965; twa prototypes haed been sent tae the Unitit States in October 1964. Caurs wur sent tae the US as unpaintit rollin chassis, an they wur finished in Shelby's workshop. Although an impressive automobile, the caur wis a financial failure an did no sell well. In fact tae save cost, maist AC Cobra 427s wur actually fittit wi Ford's 428 in³ (7.0 L) ingine, a lang stroke, smawer bore, lawer cost ingine, intendit for road uise rather than racin. It seems that a total o 300 Mark III caurs wur sent tae Shelby in the USA during the years 1965 an 1966, includin the competition version. 27 sma' block narrow fender version which wur referred tae as the AC 289 wur sold in Europe. Unfortunately, The MK III missed homologation for the 1965 racin season an wis na raced bi the Shelby team. Houever, it wis raced successfully bi mony privateers an went on tae win races aw the way intae the 70s. Interestingly, 31 unsold competition caurs wur detuned an made road worthy an cawed S/C for semi-competition. Today, these ar the rarest an the maist valuable models an can sell for in excess o 1.5 million dollars.
The AC 427 (i.e. the Mark III) dimensions wur: overall length o 14.583 feet (4.445 m), oweraw width o 5.583 ft (1.702 m), height (wi its removable top in place) o 4.250 ft (1.295 m), turnin circle o 34 ft (10.363 m), wheelbase o 8.00 feet (2.438 m), front track o 4.50 ft (1.372 m) an rear track o 4.417 ft (1.346 m). Its fuel tank held 18 imperial gallons an its empty weight wis approximately 2,300 lb (1044 kg).
AC Cobras haed an extensive racin career. Shelby wanted it tae be a "Corvette-Beater" an at nearly 500 lb less than the Chevrolet Corvette, the lichtweight caur did just that. The Cobra wis perhaps too successful as a performance caur an reputedly contributed aeo the implementation o naitional speed limits in the Unitit Kinrick. An AC Cobra Coupe wis calculated tae hae done 186 mph on the M1 motorway in 1964, driven bi Jack Sears an Peter Bolton during shakedown tests prior tae that year's Le Mans 24h race.. However, government offeecials hae cited the increasing accident daith rate in the early 1960s as the principal motivation, wi the exploits o the AC Cars team merely hichtlichtin the risk.
Although successful in racin, the AC Cobra wis a financial failure, which led Ford an Carroll Shelby tae discontinue importin caurs frae Ingland in 1967. AC Caurs kept producin the coil spring AC Roadster wi narrow fenders, a sma' block Ford 289 an called the caur the AC 289. It wis built an sold in Europe till late 1969. This caur wi modifications woud appear again in 1982 as the Autokraft MkIV, basically an AC MkIII caur wi a 5.0L Ford V8 an Borg Warner T5 Transmission. AC also produced the AC Frua till 1973. The AC Frua wis built on a stretched Cobra 427 MK III coil spring chassis uisin a vera angular handsome steel body designed an built bi Pietro Frua. Wi the demise o the Frua, AC went on building lesser caurs an eventually fell intae bankruptcy in the late 1970s'. The company's toolin an eventually the right tae uise the name, wur licensed bi Autocraft, a Cobra parts reseller an replica caur manufacturer awned bi Brian A. Angliss. Autocraft wis manufacturing an AC 289 continuation caur called the Mark IV. Shortly thereafter, Carroll Shelby filed suit against AC Caurs an Brian A. Angliss, in U.S. District Court in Los Angeles. The ensuin settlement resultit in Shelby an AC Cars/Angliss releasin a joint press release wherebi AC/Angliss acknowledged that Carroll Shelby wis (an is) the manufacturer o record o all the 1960s AC Cobra automobiles in the Unitit States an that Shelby himself is the sole person allowed tae caw his caur a Cobra. Carroll Shelby's company Shelby Automobiles, Inc. continues tae manufacture the Shelby Cobra FIA 289 an 427 S/C vehicles in various forms at its facility in Las Vegas, Nevada. These caurs retain the general style an appearance o their original 1960s ancestors, but ar fittit wi modern amenities.
In an effort tae improve top speed alang the legendary Mulsanne Straight at the 24 Hours o Le Mans race, a number o enclosed, coupe variations wur constructit uisin the leafspring chassis an runnin gear o the AC/Shelby Cobra Mark II. The maist famous an numerous o these wur the offeecial works Shelby Daytona Cobra Coupes. Sax wur constructit in total, each being subtly different frae the rest. AC also produced a Le Mans coupe. The caur wis a ane-off an wis nearly destroyed efter a hie-speed tire blow-oot at the 1964 Le Mans race. The caur wis completely rebuilt an as o now is in private awnership in Ingland. The third significant Cobra-based coupe wis the Willment Cobra Coupe built bi the JWA racin team. A road-goin Shelby Daytona Cobra replica is being manufactured bi Superformance an Factory Five Racing, a well kent kit caur company. These caurs uise Pete Brock's bodywork designs, scaled up tae increase room inside, an a newly designed spaceframe chassis, they ar pouered bi Roush-built Ford Windsor (Sportsman) ingines. The Superformance Shelby Daytona Coupe is the anerlie modern-day vehicle recognized bi Shelby as a successor tae the original Coupes.
Frae the late 1980s onwards, Carroll Shelby an associated companies hae built what ar kent in the hobby as "Continuation Caurs", Shelby authorized continuations o the original AC bodied Shelby Cobra series. Initially the caur everyane wantit in a Continuation wis a 427 S/C model which wis representit in the CSX4000 series. This wis meant tae continue where the last 427 S/C production left off, at approximately serial number CSX3560 in the 1960s.
The initial CSX4000 series caurs wur completit frae new auld stock as well as newly manufactured parts. Gradually as the vintage parts supply ran law, newly constructed frames an body panels wur obtained frae a variety o suppliers. The production o chassis numbers CSX4001 tae CSX4999 took roughly 20 years an mony different business relationships tae complete.
Aw models o Cobra produced ar available nou as continuations. In 2009, CSX4999 wis produced, concludin the 4000 series. Production haes continued wi the CSX6000 serial numbers, featurin "coil over" suspension. The 289 FIA "leaf spring" race version o the caur is reproduced as CSX7000, an the original "slab side" leaf spring street caur is the CSX8000 series.
To date maist continuations ar produced in fiberglass, wi some orderin caurs wi aluminum or carbon fibre bodywork.
In 2004, at the North American Internaitional Auto Show in Detroit, Ford unveiled a concept for a modernized Shelby Cobra. The Ford Shelby Cobra Concept wis a continuation o Ford's effort tae bring back the retro sports caurs that haed been successful in the 1960s, includin the Ford GT40 an the fift generation Ford Mustang.
Shelby Motors built twintie twa 427 competition roadsters. In 1965, ane wis selectit an convertit intae a special model called the 427 "Cobra tae End Aw Cobras." The first ane o these (number CSX3015) wis originally part o a European promotional tour afore its conversion. This conversion cawed for makin the original racin model street legal wi mufflers, a windshield an bumpers amangst ither modifications. But some things wur no modified, includin the racin rear end, brakes an headers. The maist notable modification is the addition o Twin Paxton Superchargers. This gave the caur a claimed 462 brake horsepouer (bhp) an 800 Ft pounds o torque at 3000 rpm. Offeecially 0 tae 60 mph wis achieved in 4.5 seconds, although there ar reports o this being achieved in little ower 3 seconds.
Anither non-competition 427 roadster, CSX3303, wis convertit an given tae Shelby's close friend, Bill Cosby. Cosby attemptit tae drive the super-fast Cobra, but haed issues wi keepin it unner control. This wis humorously documentit in Cosby's album titled Bill Cosby, 200 M.P.H.. Cosby gave the caur back tae Shelby, who then shipped it oot tae ane o their dealers in San Francisco, S&C Ford on Van Ness Avenue. S&C Ford then sold it tae customer Tony Maxey. Maxey, sufferin the same issues as Cosby did wi the caur, lost control an drove it off o a cliff, landin in the Paceefic Ocean waters. It is tae be notit that Maxey's accident wis lairgely speculatit as suicide. It wis eventually recovered an the wreckage wis bought bi Brian Angliss o AC/Autokraft. Since CSX3303 wis so badly damaged in the Maxey accident, it is doubtful that muckle o the original caur will surface in the restored version.
Shelby's original model, CSX3015, wis kept bi Carroll Shelby himself ower the years as a personal caur, sometimes enterin it intae local races like the Turismos Visitadores Cannonball-Run race in Nevada, where he wis "wakin [up] whole touns, blowin oot windows, throwin belts an catchin fire a couple o times, but finishin." CSX3015 wis auctioned off on 22 Januar 2007 at the Barrett-Jackson Collector Caur Event in Scottsdale, Arizona for $5 million plus commission. This woud be a record for Cobras, as well as for a Barrett-Jackson sell price.
- Friedman, Dave: "Shelby Cobra: the Shebly American color archives", chapter 1, MBI Publishing Company, ISBN 0-87938-757-2
- "185mph on the British motorway in 1963 - the real story from Jack Sears". classicdriver.com. Retrieved 2008-01-04.
- "Barrett-Jackson Lot: 1301 - 1966 SHELBY COBRA 427 "SUPER SNAKE"". barrett-jackson.com.