AC Cobra

Shelby Cobra redirects here. See also the Shelby Mustang Cobra
AC Cobra
An artists rendering of the first AC Cobra, with the 260in³ engine. Note the narrower track and smaller wheelarches with flattened lips
Manufacturer AC Cars
Production 1961-1967
Assembly Thames Ditton, Surrey, England
Body style(s) 2-door roadster
Layout FR layout
First generation
1961 Shelby AC Cobra
Production 1961-1962
Engine(s) 5.1L V8
4.2L V8
2.6L I6
4.7L V8
Second generation
Production 1963-1964
Engine(s) 7.0L V8
Third generation
Production 1965-1967
Engine(s) 7.0L V8

The AC Cobra was a British built and designed sports car that was produced during the 1960s.

Contents

History and development

AC Shelby Cobra

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. Although untrue, it is commonly believed that AC was left without a future source of power and that American ex-racing driver Carroll Shelby saved the company from bankruptcy. AC started using the 2.6 litre Ford Zephyr in all of its cars. In September 1961, Shelby airmailed AC a letter asking them if they would build him a car modified to accept a V8 engine. Shelby had previous experience with Anglo-American hybrids, having raced an Allard. He first went to Chevrolet to see if they would provide him with engines, but not wanting to add competition to the Corvette they said no. Ford however, wanted a car that could compete with the Corvette and they happened to have a brand new thin wall small block engine which could be used in this endeavor.

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 January 1962 mechanics at AC Cars in Thames Ditton, Surrey fitted the prototype chassis CSX0001 with a 221ci Ford V8. After testing and modification, the engine and transmission was taken out and the chassis was air freighted to Caroll Shelby in Los Angeles on 2 February 1962.[1] Here it was fitted with an engine and transmission in less than eight hours and taken out on test.

Production proved to be easy, since AC had already made most of the modifications needed for the small block V8 when they installed the 2.6 litre Ford Zephyr engine, including the extensive rework of the AC Ace's front end. The most important modification was the fitting of a stronger rear differential to handle the power of the Ford V8. A Salisbury 4HU unit with in-board disk brakes to reduce unsprung weight was chosen instead of the old ENV unit. It was the same unit used on the Jaguar E-Type. On the production version, the inboard brakes were moved outboard to reduce cost. The only modification of the front end of the first Cobra from that of the AC Ace 2.6 was the mounting of the steering box, which had to be moved outward to clear the wider V8 motor.

Badge

The first 75 Cobra Mark I (including the prototype) were fitted with the 260 engine (4.2 L). The remaining 51 Mark I model were fitted with a larger version of the Windsor Ford engine, the 289 in³ (4.7 L) V8. Toward the end of 1962, Alan Turner who was the chief engineer at AC completed a major design change of the car's front end and was able to fit it with Rack and pinion steering while still using transverse leaf springs suspension. The new car went into production in early 1963 and it became known as the Mark II. The steering rack was borrowed from the MGB while the new steering column came from the VW Beetle. About 528 Mark II Cobras were produced to the summer of 1965 (the last US bound Mark II was produced in November 1964).

By 1963 the leaf spring Cobra was losing its supremacy in racing, Shelby tried fitting a big Ford FE engine of 390 in³. Ken Miles drove and raced the FE powered Mark II car and said that the car was virtually undrivable, naming it 'The Turd'. A new chassis was developed and designated the Mark III.

Shelby AC Cobra

The new car was designed in cooperation with Ford in Detroit. A whole new chassis was built 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. It was powered by the famed "side oiler" Ford 427 engine (7.0 L) developing 425 bhp (317 kW) and attaining a top speed of 163 mph (262 km/h) in the standard model and 485 bhp (362 kW) with a top speed of 180 mph (290 km/h) in the competition model. The production of the Cobra Mark III began on 1 January 1965, two prototypes had been sent to the United States in October of 1964. Cars were sent to the US as unpainted rolling chassis, and they would be finished in Shelby's workshop. Although an impressive automobile, the car was a financial failure and did not sell well. In fact to save cost, most AC Cobra 427's were actually 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. It seems that a total of 300 Mark III cars were sent to Shelby in the USA during the years 1965 and 1966, including the competition version. 27 small block narrow fender version which were referred to as the AC 289 were sold in Europe. Unfortunately, The MK III missed homologation for the 1965 racing season and was not raced by the Shelby team. However, it was raced successfully by many privaters and went on to win races all the way into the 70's. Interestingly, 31 unsold competition cars were detuned and made road worthy and called S/C for semi-competition. Today, these are the rarest and the most valuable models and can sell for in excess of 1.5 million dollars.

AC Cobras had an extensive racing career. Shelby wanted it to be a "Corvette-Beater" and at nearly 500 lb (227 kg) less than the Chevrolet Corvette, the lightweight car did just that. The Cobra was perhaps too successful as a performance car and reputedly contributed to the implementation of national speed limits in the United Kingdom. An AC Cobra Coupe was calculated to have done 185 mph (298 km/h) 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.[2] 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.

Although extremely successful in racing, The AC Cobra was a financial failure, which led Ford and Carroll Shelby to discontinue importing cars from England in 1967. AC Cars kept producing the coil spring AC Roadster with narrow fenders, a small block Ford 289 and called the car the AC 289, it was built and sold in Europe until late 1969. This car with modifications would appear again in 1982 as the Autokraft MkIV, basically an AC MkIII car with a 5.0L Ford V8 and Borg Warner T5 Transmission. AC also produced the AC Frua until 1973. The AC Frua was built on a stretched Cobra 427 MK III coil spring chassis using a very angular handsome steel body designed and built by Pietro Frua. With the demise of the Frua, AC went on building lesser cars and eventually fell into bankruptcy in the late 1970s'. The company's tooling and eventually the right to use the name, were licensed by Autocraft, a Cobra parts reseller and replica car manufacturer owned by Brian A. Angliss. Autocraft was manufacturing an AC 289 continuation car called the Mark IV. Shortly thereafter, Carroll Shelby filed suit against AC Cars and 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 acknowledged that Carroll Shelby was (and is) the manufacturer of record of all the 1960s AC Cobra automobiles in the United States and that Shelby himself is the sole person allowed to call his car a Cobra. Despite this there is no doubt that every Cobra made in the '60s was manufactured by AC Cars in England, shipped to Shelby for completion. Carroll Shelby's company Shelby Automobiles, Inc. continues to manufacture the Shelby Cobra FIA 289 and 427 S/C vehicles in various forms at its facility in Las Vegas, Nevada. These cars retain the general style and appearance of their original 1960s ancestors, but are fitted with modern amenities. In 2006 Carol Shelby's own Shelby Cobra sold at an auction in Arizona for £2.8million.[3]

Coupes or Coupé

Peter Brock's Daytona Sportscar on the day before his fatal accident

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 leafspring chassis and running gear of the AC/Shelby Cobra Mark II. 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. AC also produced a Le Mans coupe, The car was a one-off and was nearly destroyed after a high-speed tire blow-out at the 1964 Le Mans race. It has now been completely rebuilt and now sits in private hands in England. The third significant Cobra-based coupe was the Willment Cobra Coupe built by the JWA racing team. Mike Mc Cluskey of Torrance California (one of the best Cobra restorers in the world), builds an exact replica of the racing Shelby Daytona coupe, these cars are exact reproductions of the originals. Also, a road-going Shelby Daytona Cobra replica is being manufactured by Superformance and Factory Five Racing, a well known kit car company. These cars use Peter Brock's bodywork designs, scaled up by to increase room inside, and a newly designed spaceframe chassis, they are powered by Roush-built Ford Windsor (Sportsman) engines. The Superformance Shelby Daytona Coupe is the only modern-day vehicle recognized by Shelby as a successor to the original Coupes. Peter Brock's Australian namesake, the race car driver, was killed while driving a GM-powered replica of a Shelby Daytona Coupe in competition in Australia in 2006.

Continuation cars

In 2003, Carroll Shelby International Inc. and AC Motor Holdings, Ltd. announced production of authentic Shelby/AC Cobra,[4] with the production vehicle arriving at dealers in July 2004.[5]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. Today, the CSX 4000, featuring "coil over" suspension, is produced in aluminum, carbon fibre, and fibreglass body styles. The FIA "leaf spring" race version of the car is reproduced as CSX 7000, and the original "slab side" buggy spring street car is the CSX 8000. The 7000 and 8000 series Cobras are available as fiberglass body cars.

Super Snake

Shelby Motors built 22 427 competition roadsters. In 1965, one was selected and converted into a special model called the 427 "Cobra to End All Cobras". The first one of these (number CSX 3015) was originally part of a European promotional tour before its conversion. This conversion called for making the original racing model street legal with mufflers, a windshield and bumpers amongst other modifications. But some things were not modified, including the racing rear end, brakes and headers. The most notable modification is the addition of Twin Paxton Superchargers. This gave the car an alleged 800 brake horsepower (bhp) and 462 lb·ft (626 N·m). of torque at an astounding low of 2800 rpm. Officially rated at 0-to-60 at 4.5 seconds, legend and lore have it as doing that in a little over 3 seconds as one must lay off the throttle heavily just to get traction off the line.

Another non-competition 427 roadster was converted, (CSX 3303), and given to Shelby's close friend, Bill Cosby. Cosby attempted to drive the super-fast Cobra, but had issues with keeping it under control. This was humorously documented in Cosby's album titled "Bill Cosby, 200 M.P.H.". Cosby then gave the car back to Shelby, who then shipped it out to one of their dealers in San Francisco, S&C Ford on Van Ness Avenue. S&C Ford then sold it to customer Tony Maxey. Maxey, suffering the same issues as Cosby did with the car, lost control and drove it off of a cliff, landing in the Pacific Ocean waters. It is to be noted that Maxey's accident was largely speculated as suicide. It was eventually recovered and the wreckage was bought by Brian Angliss of CP Autokraft. He is expected to auction his restored version in the future.

Shelby's original model, CSX 3015, was kept by Carroll Shelby himself over the years as a personal car, sometimes entering it into local races like the Turismos Visitadores Cannonball-Run race in Nevada, where he was "waking [up] whole towns, blowing out windows, throwing belts and catching fire a couple of times, but finishing." CSX 3015 was auctioned off on 22 January 2007 at the Barrett-Jackson Collector Car Event in Scottsdale, Arizona for $5 million plus commission (a record for Cobras, and a record for a Barrett-Jackson sold price).

In popular culture

Notes

  1. Friedman, Dave: "Shelby Cobra: the Shebly American color archives", chapter 1, MBI Publishing Company, ISBN 0-87938-757-2
  2. "185mph on the British motorway in 1963 - the real story from Jack Sears". classicdriver.com. Retrieved on 2008-01-04.
  3. "Car goes for £2.8million". thesun.co.uk. Retrieved on 2008-01-04.
  4. "Shelby And AC Sign Definitive Agreement To Join Forces". carrollshelby.com via web.archive.org. Retrieved on 2008-01-04.
  5. "Shelby and AC Gear Up for 2005 Shelby AC Cobra". motortrend.com. Retrieved on 2008-01-04.
  6. http://www.gamewinners.com/MAC/AgeOfEmpires2Gold.htm

'Running from the guns.' (1987 Australian movie with a yellow Cobra.)

'American Graffiti.' released 1973, 289 Cobra roadster.

External links

Parts, Restoration and Replica manufacturers