AC Cobra

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427 AC Shelby America CSX 4109 Cobra Signature Series #3 of 4

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Shelby Cobra redirects here. See also the Shelby Mustang Cobra

The AC Cobra was a British sports car built in the 1960s. It was not the first car to combine a lightweight European chassis and aluminium body with a big American V8 engine, but it is possibly the most famous. The later, larger-engined cars are still among the highest-performing road vehicles ever sold.

1 History and Development
2 Covered Cobras
3 Shelby Cobra (2004 - )
4 AC MK V
- 4.1 Suggested Specifications
- 4.2 Specifications (USA)
5 Replicas
6 External links
7 Movie Appearances

[edit] History and Development

Like many British specialist manufacturers, AC Cars had been using the smooth, refined Bristol straight-6 engine in its small-volume production, including its AC Ace 2-seater roadster. The engine was a pre-World War II design of BMW which by the 60s the company knew was considered dated. Bristol decided in 1961 to cease production of its engine and instead to use Chrysler 313cid (5.1 L) V8 engines. AC was left without a future source of power. Into this void stepped American ex-racing driver Carroll Shelby, who in September 1961 airmailed AC a proposal to ship its engineless cars to Shelby's California works to be fitted with American V8s. Shelby had previous experience with Anglo-American hybrids, having raced an Allard.

An artists rendering of the first AC Cobra, with the 260in³ engine. Note the narrower track and smaller wheelarches with flattened lips

AC agreed, provided a suitable engine could be found. It was, in the form of, Ford's 260 in³ HiPo (4.2 L) engine - a new lightweight, thin-wall cast small-block V8 tuned for high performance. In early 1962 the first engineless AC Ace was air-freighted to Shelby's Los Angeles facility, where it was fitted with an engine and transmission in less than eight hours and taken out on test. Carroll Shelby claims the name "Cobra" came to him in a dream.

Production proved to be less easy; the AC chassis needed extensive work to take the Ford drivetrain, and at first, the cars were slow to be produced. Soon a larger version of the Windsor Ford engine, the 289 in³ (4.7 L) V8 was fitted. AC Cobras began an extensive racing career with this engine, which boosted power to 271 hp (202 kW) and gave it a new top speed of 140 mph (225 km/h). The same engine was used by Shelby American in its high performance version of the Mustang; the GT350.

It proved to be a great performance success; the automobile had originally been designed by Shelby with the intention it would be a "Corvette-Beater" and at nearly 500lbs. less than the Chevrolet Corvette, the lightweight car did just that. The Cobra was perhaps too successful in the performance department and reputedly contributed to the implementation of national speed limits in the United Kingdom. The 427 in³-engined AC Cobra Coupe was calculated to have done 185mph on the M1 motorway in 1964, driven by Jack Sears and Peter Bolton during shakedown tests prior to that year's Le Mans 24h race [1]. However, government officials have cited the increasing accident death rate in the early 1960s as the principal motivation, the exploits of the AC Cars team just highlighting the potential risk.

1999 AC Cobra 427

1964 saw an even larger engine fitted; Ford's famed 427 in³ racing engine (7.0 L) developing 485 bhp (362 kW) and attaining a top speed of 163 mph (262 km/h). Even more extensive rework of the AC design was needed to accomplish this; the big-block FE-series engine was much too heavy to work in a standard MK2 car. Ken Miles drove and raced an FE powered MK2 car and said that the car was virtually undrivable! A whole new chassis was designed with the help of Ford computers which featured 4" main chassis tubes (instead of 3") and coil spring suspension all around. the new car also had wide fenders and a larger radiator opening. To save cost, some AC Cobras MK3 were fitted with Ford's 428 in³ (7.0 L) engine, a long stroke, smaller bore, lower cost engine, intended for road use rather than racing.

AC Cars stopped producing the Roadster platform on which the Cobra was built in 1968, at which point Shelby stopped producing Cobras. Decades later Carroll Shelby filed suit against AC Cars and its proprietor, Brian A. Angliss, in U.S. District Court in Los Angeles. The ensuing settlement resulted in Shelby and AC Cars/Angliss releasing a joint press release whereby AC/Angliss acknowledge that Carroll Shelby was (and is) the manufacturer of record of all the 1960s AC Cobra automobiles. Despite this there is no doubt that every Cobra made in the '60s was manufactured by AC Cars in England. Shelby merely modified the cars into their final form. Carroll Shelby's company Shelby Automobiles, Inc. continues to manufacture the Shelby Cobra 289, FIA 289 and 427 S/C vehicles at its facility in Las Vegas, Nevada. These cars retain the style and appearance of their original 1960s ancestors, but are fitted with all the modern amenities.

AC Cobra

The Cobra is probably the most cloned car in history; an astounding number of replica Cobras have been produced, to the extent that the originals are in a minority. Some are Cobra lookalikes, while others are perfect replicas in every detail like the Kirkham built in Poland by aircraft engineers in an old MiG factory. These cars are exact replicas of the originals except that they are built with higher standards.

In 2004, Sports Car International named this car number two on the list of Top Sports Cars of the 1960s.

Shelby worked with the Chrysler Corporation from 1989 to 1991 to help develop and style the Viper supercar and in the late 1990s, developed his own Series 1, a composite-bodied high performance car powered by the 4.0 L, DOHC, 32-valve V8 from the Oldsmobile Aurora luxury sedan producing 320 hp (239 kW). A more powerful supercharged version was available in limited quantities as well. The Viper and Series 1 are considered to be the succesors to the Cobra, although the Series 1 was/is more like the Cobra than the Viper is.

[edit] Covered Cobras

Peter Brock's Daytona Coupé - photo taken the day before the accident in which he was killed

In an effort to improve top speed along the legendary Mulsanne Straight at the 24 Hours of Le Mans race, a number of enclosed, coupe variations were constructed using the chassis and running gear of the AC/Shelby Cobra. The most famous and numerous of these were the official works Shelby Daytona Cobra Coupes. Six were constructed in total, each being subtly different from the rest. Also famous, although infamous may be a more accurate word, is the AC Cobra Coupe: the car often credited with hastening the introduction of motorway speed limits in the UK. The car was a one-off and was destroyed after a high-speed tyre blow-out at the 1964 Le Mans race. The third significant Cobra-based coupe was the Willment Cobra Coupe built by the JWA racing team. Currently, road-going Shelby Daytona Cobras are being manufactured by the Hi-Tech Automotive company in South Africa by Superformance under license from Shelby. These cars use Peter Brock's original bodywork designs, scaled up by 2% to increase room inside, and a newly designed spaceframe chassis. Brock's Australian namesake, the race car driver, was killed while driving an unlicensed GM-powered replica of a Shelby Daytona Coupe in competition in Australia in 2006.

[edit] Shelby Cobra (2004 - )

In 2003, Carroll Shelby International Inc. and AC Motor Holdings, Ltd. announced production of authentic Shelby/AC Cobra[2], with the production vehicle arriving at dealers in July 2004[3]. Initially available models included Shelby AC 427 S/C Cobra and Shelby AC 289 FIA Cobra, which will be branded as the CSX 1000 and CSX 7500 Series, respectively. In February 2004 the first handcrafted aluminum body shell was built. However, AC Motor Holdings, Ltd. failed to perform under the terms of its license agreement with Carroll Shelby, and a lawsuit was filed by Shelby against AC Motor Holdings, Ltd. and its proprietor, Alan Lubinsky, in May 2006.

[edit] AC MK V

The 'production' AC MK V is sold without an engine or transmission. The buyer can choose options suggested by the distributor.

[edit] Suggested Specifications

Engine head	Cast head	Aluminium head
displacement	302ci (4949 cc), 351ci (5752 cc)	302ci (4949 cc), 342ci (5604 cc), 347ci (5686 cc)
horsepower	225-250 (168-186 kW)	315-450 (235-336 kW)
torque (lb-ft)	300-? (407-? N m)	295-400 (400-542 N m)
stroke (in), crank type	3-3.5 (76-89 mm) cast	3-3.4 (76-86 mm) cast, 3.4 (86 mm) forged
compression ratio	8.5-9	9-10

[edit] Specifications (USA)

The AC MK V runs on a fuel injected 5.0 L Ford V8 engine rated at 340 hp (254 kW) and 310 ft·lbf (420 N m) of torque at 3750 rpm, a 5-speed manual transmission, limited slip differential, 16 in (41 cm) wheels, leather interior, wool interior carpeting, carbon fiber body panels on a tubular steel chassis.