Sunbeam Tiger Mk II 1967 |
The Sunbeam Tiger is a high-performance V8 version of the British Rootes Group's Sunbeam Alpine roadster, designed in part by American car designer and racing driver Carroll Shelby and produced from 1964 until 1967. Shelby had carried out a similar V8 conversion on the AC Cobra, and hoped to be offered the contract to produce the Tiger at his facility in America. Rootes decided instead to contract the assembly work to Jensen at West Bromwich in England, and pay Shelby a royalty on every car produced.
Two major versions of the Tiger were built: the Series I (1964–67) was fitted with the 260 cu in (4.3 L) Ford V8; the Series II, of which only 633 were built in the final year of Tiger production, was fitted with the larger Ford 289 cu in (4.7 L) engine. Two prototype and extensively modified versions of the Series I competed in the 1964 24 Hours of Le Mans, but neither completed the race. Rootes also entered the Tiger in European rallies with some success, and for two years it was the American Hot Rod Association's national record holder over a quarter-mile drag strip.
Sunbeam Tiger Convertible 1965 |
Production ended in 1967 soon after the Rootes Group was taken over by Chrysler, which did not have a suitable engine to replace the Ford V8. Owing to the ease and affordability of modifying the Tiger, there are few surviving cars in standard form.
The Sunbeam Tiger was a development of the Sunbeam Alpine, introduced by the British manufacturer Rootes in 1953. Rootes realised that the Alpine needed more power if it was to compete successfully in world markets, but lacked a suitable engine and the resources to develop one. The company therefore approached Ferrari to redesign the standard inline-four cylinder engine, recognising the sales cachet that "powered by Ferrari" would be likely to bring. Negotiations initially seemed to go well, but ultimately broke down.
Sunbeam Tiger Mk I 1966 |
In 1962 racing driver and Formula 1 champion Jack Brabham proposed to Rootes competition manager Norman Garrad the idea of fitting the Alpine with a Ford V8 engine, which Garrad relayed to his son Ian, then the West Coast Sales Manager of Rootes American Motors Inc. Ian Garrad lived close to where Carroll Shelby had his Shelby American operation, which had done a similar V8 conversion for the British AC Cobra.
According to journalist William Carroll, after measuring the Alpine's engine bay with "a 'precision' instrument of questionable antecedents" – a wooden yardstick – Ian Garrad despatched his service manager Walter McKenzie to visit the local new car dealerships, looking for a V8 engine that might fit. McKenzie returned with the news that the Ford 260 V8 engine appeared to be suitable, which apart from its size advantage was relatively light at 440 lb (200 kg). Ian Garrad asked Shelby for an idea of the timescale and cost to build a prototype, which Shelby estimated to be eight weeks and $10,000. He then approached Brian Rootes, head of sales for the Rootes Group, for funding and authorisation to build a prototype, to which Brian Rootes agreed.
Sunbeam Tiger Prototype Roadster 1964 |
Ian Garrad, impatient to establish whether the conversion was feasible, commissioned racing driver and fabricator Ken Miles to build another prototype as quickly as he could. Miles was provided with a budget of $800, a Series II Alpine, a Ford V8 engine and a 2-speed automatic transmission, and in about a week he had a running V8 conversion, thus proving the concept.
Shelby began work on his prototype, the white car as it came to be known, in April 1963, and by the end of the month it was ready for trial runs around Los Angeles. Ian Garrad and John Panks, director of Rootes Motors Inc. of North America, tested an early version of the car and were so impressed that Panks wrote a glowing report to Brian Rootes: "we have a tremendously exciting sports car which handles extremely well and has a performance equivalent to an XX-K Jaguar ... it is quite apparent that we have a most successful experiment that can now be developed into a production car."
Sunbeam Tiger Mk II 1967 |
Provisionally known as the Thunderbolt, the Shelby prototype was more polished than the Miles version, and used a Ford 4-speed manual transmission. The Ford V8 was only 3.5 inches longer than the Alpine's 4-cylinder engine it replaced, so the primary concern was the engine's width. Like Miles, Shelby found that the Ford V8 would only just fit into the Alpine engine bay: "I think that if the figure of speech about the shoehorn ever applied to anything, it surely did to the tight squeak in getting that 260 Ford mill into the Sunbeam engine compartment. There was a place for everything and a space for everything, but positively not an inch to spare."
Sunbeam Tiger Mk I 1966 |
All Rootes products had to be approved by Lord Rootes, who was reportedly "very grumpy" when he learned of the work that had gone into the Tiger project without his knowledge. But he agreed to have the Shelby prototype shipped over from America in July 1963 for him and his team to assess. He insisted on driving the car himself, and was so impressed that shortly after returning from his test drive he contacted Henry Ford II directly to negotiate a deal for the supply of Ford V8 engines. Rootes placed an initial order for 3000, the number of Tigers it expected to sell in the first year, the largest single order Ford had ever received for its engines from an automobile manufacturer. Not only did Lord Rootes agree that the car would go into production, but he decided that it should be launched at the 1964 New York Motor Show, only eight months away, despite the company's normal development cycle from "good idea" to delivery of the final product being three to four years.
Sunbeam Tiger Prototype Roadster 1964 |
Installing such a large engine in a relatively small vehicle required some modifications, although the exterior sheet metal remained essentially the same as the Alpine's. Necessary chassis modifications included moving from the Burman recirculating ball steering mechanism to a more modern rack and pinion system.
Although twice as powerful as the Alpine, the Tiger is only about twenty per cent heavier, but the extra weight of the larger engine required some minor suspension modifications. Nevertheless the Tiger's front-to-back weight ratio is substantially similar to the Alpine's, at 51.7/48.3 front/rear.
Sunbeam Tiger Mk II 1967 |
Shortly before its public unveiling at the New York Motor Show in April 1964 the car was renamed from Thunderbolt to Tiger, inspired by Sunbeam's 1925 land-speed-record holder.
Shelby had hoped to be given the contract to produce the Tiger in America, but Rootes was somewhat uneasy about the closeness of his relationship with Ford, so it was decided to build the car in England. The Rootes factory at Ryton did not have the capacity to build the Tiger, so the company contracted the job to Jensen in West Bromwich. Any disappointment Shelby may have felt was tempered by an offer from Rootes to pay him an undisclosed royalty on every Tiger built.
Jensen was able to take on production of the Tiger because its assembly contract for the Volvo P1800 had recently been cancelled. An additional factor in the decision was that Jensen's chief engineer Kevin Beattie and his assistant Mike Jones had previously worked for Rootes, and understood how the company operated. The first of 14 Jensen-built prototypes were based on the Alpine III bodyshell, until the Series IV became available at the end of 1963.
Sunbeam Tiger Mk I 1966 |
The Tiger went into production in June 1964, little more than a year after the completion of the Shelby prototype. Painted and trimmed bodies were supplied by Pressed Steel in Oxfordshire, and the engines and gearboxes directly from Ford in America. Installing the engine required some unusual manufacturing methods, including using a sledgehammer to bash in part of the already primed and painted bulkhead to allow the engine to be slid into place. Jensen was soon able to assemble up to 300 Tigers a month, which were initially offered for sale only in North America. The first few Tigers assembled had to be fitted with a Borg-Warner 4-speed all-synchromesh manual gearbox, until Ford resolved its supply problems and was able to provide an equivalent unit as used in the Ford Mustang.
Sunbeam Tiger Prototype Roadster 1964 |
Several performance modifications were available from dealers. The original 260 CID engine was considered only mildly tuned at 164 hp (122 kW), and some dealers offered modified versions with up to 245 hp (183 kW) for an additional $250. These modifications were particularly noticeable to the driver above 60 mph (97 km/h), although they proved problematic for the standard suspension and tyres, which were perfectly tuned for the stock engine. A 1965 report in the British magazine Motor Sport concluded that "No combination of an American V8 and a British chassis could be happier."
Sunbeam Tiger Mk II 1967 |
Production reached 7128 cars over three distinct series. The factory only ever designated two, the Series I and Series II, but as the official Series I production spanned the change in body style from the Series IV Alpine panels to the Series V panels, the later Series I cars are generally designated Series IA by Sunbeam Tiger enthusiasts. The Series II Tiger, fitted with the larger Ford 289 cu in (4.7 L), was intended exclusively for export to America and was never marketed in the UK, although six right-hand drive models were sold to the Metropolitan Police for use in traffic patrols and high-speed pursuits; four more went to the owners of important Rootes dealerships.
Sunbeam Tiger Mk I 1966 |
All Tigers were fitted with a single Ford twin-choke carburettor. The compression ratio of the larger Series II engine was increased from the 8.8:1 of the smaller block to 9.3:1. Other differences between the versions included upgraded valve springs (the 260 had developed a reputation for self-destructing if pushed beyond 5000 rpm), an engine-oil cooler, an alternator instead of a dynamo, a larger single dry plate hydraulically operated clutch, wider ratio transmission, and some rear-axle modifications. There were also cosmetic changes: speed stripes instead of chrome strips down the side of the car, a modified radiator grille, and removal of the headlamp cowls. All Tigers were fitted with the same 4.5 in (110 mm) wide steel disc bolt-on wheels as the Alpine IV, and Dunlop RS5 4.90 in × 13 in (124 mm × 330 mm) cross-ply tyres. The lack of space in the Tiger's engine bay causes a few maintenance problems; the left bank of spark plugs is only accessible through a hole in the bulkhead for instance, normally sealed with a rubber bung, and the oil filter had to be relocated from the lower left on the block to a higher position on the right-hand side, behind the generator.
Series I
Sunbeam Tiger Prototype Roadster 1964 |
The Ford V8 as fitted to the Tiger produced 164 bhp (122 kW) @ 4400 rpm, sufficient to give the car a 0–60 mph (97 km/h) time of 8.6 seconds and a top speed of 120 mph (190 km/h).
The Girling-manufactured brakes used 9.85 in (250 mm) discs at the front and 9 in (229 mm) drums at the rear. The suspension was independent at the front, using coil springs, and at the rear had a live axle and semi-elliptic springs. Apart from the addition of a Panhard rod to better locate the rear axle, and stiffer front springs to cope with the weight of the V8 engine, the Tiger's suspension and braking systems are identical to that of the standard Alpine. The fitting points for the Panhard rod interfered with the upright spare wheel in the boot, which was repositioned to lie horizontally beneath a false floor; the battery was moved from beneath the rear seat to the boot at the same time. The kerb weight of the car increased from the 2,220 lb (1,010 kg) of the standard Alpine to 2,653 lb (1,203 kg).
In 1964, its first year of production, all but 56 of the 1649 Series I Tigers assembled were shipped to North America, where it was priced at $3499. In an effort to increase its marketability to American buyers the car was fitted with "Powered by Ford 260" badges on each front wing beneath the Tiger logo. The Series I was unavailable in the UK until March 1965, when it was priced at £1446. It was also sold in South Africa for R3350, badged as the Sunbeam Alpine 260.
Series II
Sunbeam Tiger Mk II 1967 |
Priced at $3842, the Series II Tiger was little more than a re-engined Mark IA; by comparison, a contemporary V8 Ford Mustang sold for $2898. The larger 289 cu in (4.7 L) Ford engine improved the Tiger's 0–60 mph (97 km/h) time to 7.5 seconds, and increased the top speed to 122 mph (196 km/h). Officially the Series II Tiger was only available in the US, where it was called the Tiger II. By the time the Series II car went into production Chrysler was firmly in charge of Rootes, and the "Powered by Ford" shields were replaced by "Sunbeam V-8" badges.
Three racing Tigers were constructed for the 1964 24 Hours of Le Mans, a prototype and two that were entered in the race.[24] Costing $45,000 each, they were highly modified versions of the production cars, fitted with fastback coupe bodies produced by Lister. But they were still steel monocoques, and made the Le Mans Tigers 66 lb (30 kg) heavier than a road-going Tiger at 2,615 lb (1,186 kg), almost 600 lb (270 kg) more than the winning Ferrari. The standard Ford four-speed manual transmission was replaced with a BorgWarner T10 close-ratio racing transmission, which allowed for a top speed of 140 miles per hour (230 km/h).
Sunbeam Tiger Prototype Roadster 1964 |
Both Tigers suffered early mechanical failures, and neither finished the race. The engines had been prepared by Shelby but had not been properly developed, and as a result overheated; Shelby eventually refunded the development cost to Rootes. All three of the Le Mans Tigers have survived.
Once Rootes had made the decision to put the Tiger into production an Alpine IV minus engine and transmission was shipped to Shelby, who was asked to transform the car into a racing Tiger. Shelby's competition Tiger made an early appearance in the B Production Class of Pacific Coast Division SCCA races, which resulted in some "highly successful" publicity for the new car. But Shelby was becoming increasingly preoccupied with development work for Ford, and so the racing project was transferred to the Hollywood Sports Car dealership, whose driver Jim Adams achieved a third place finish in the Pacific Coast Division in 1965. A Tiger driven by Peter Boulton and Jim Latta finished twelfth overall and first in the small GT class at the 1965 Dayton Continental. The Tiger was also raced on quarter-mile drag strips, and for two years was the American Hot Rod Association's national record holder, reaching a speed of 108 mph (174 km/h) in 12.95 seconds.
Sunbeam Tiger Mk II 1967 |
Rootes entered the Tiger in European rallies, taking first, second and third places in the 1964 Geneva Rally. Two Tigers took part in the 1965 Monte Carlo Rally, one finishing fourth overall, the highest placing by a front-engined rear-wheel drive car, and the other eleventh. After finally having sorted out the engine overheating problem by fitting a forward-facing air scoop to the bonnet, Rootes entered three Tigers in the 1965 Alpine Rally, one of which crossed the finishing line as outright winner. Scrutineers later disqualified the car however, because it had been fitted with undersized cylinder head valves. By the end of the 1966 Acropolis Rally though, it had become clear that low-slung sports cars such as the Tiger were unsuited to the increasingly rough-terrain rally stages, and the car was withdrawn from competition soon after. In the words of Ian Hall, who drove the Tiger in the Acropolis Rally, "I felt that the Tiger had just had it – it was an out of date leviathan".
Sunbeam Tiger Prototype Roadster 1964 |
The 1965 Tiger Series I gained some exposure on American television as the car of choice for Maxwell Smart in the spoof spy series Get Smart. The Tiger was used for the first two seasons in the opening credits, in which Smart screeched to a halt outside his headquarters, and was used through the remainder of the series in several episodes. Some of the scenes featured unusual modifications such as a retractable James Bond-style machine gun that could not have fitted under the Tiger's bonnet, so rebadged Alpine models were used instead.
Don Adams, who played the protagonist Maxwell Smart, gained possession of the Tiger after the series ended and later gave it to his daughters; it is reportedly on display at the Playboy Mansion in Los Angeles. During its early years Rootes advertised the car extensively in Playboy magazine and lent a pink Tiger with matching interior to 1965 Playmate of the Year Jo Collins for a year.
The Tiger also featured in the 2008 film adaptation of the Get Smart TV series. A replica Tiger had to be constructed using a stock Sunbeam Alpine and re-created Tiger badging as no available Tiger could be found in Canada, where the film was produced. The production team recorded the sound of an authentic Tiger owned by a collector in Los Angeles and edited it into the film.
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