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|Let Me Be Your Little Wheel: The Original BMC Mini|
|Written by Aaron Severson|
|Saturday, 01 May 2010 00:00|
Page 1 of 4
The BMC Mini is one of a tiny handful of vehicles that are truly iconic, immediately recognizable even by people who know nothing about cars. It's as enduring a symbol of sixties Britain as the Beatles and James Bond -- a revolutionary little shoebox on wheels that rewrote the rules for compact cars.
THE BUBBLECAR INVASION
Just as the first Big Three compacts of 1960 emerged from the "Eisenhower Recession" of 1957-1958, the Mini was born in crisis. In October 1956, the British and French governments made a secret agreement with Israel to retake the Suez Canal, which Egyptian president Gamal Abdel Nasser had nationalized that summer. Israeli armed forces advanced into the Sinai Peninsula, providing a pretense for an Anglo-French task force, dubbed Operation Musketeer, to invade Egypt, ostensibly to ensure the security of the Canal Zone. However, both the United States and the Soviet Union refused to support the invasion and U.S. President Dwight Eisenhower exerted strong economic pressure on Great Britain to withdraw, nearly collapsing the British pound in the process. The Musketeer task force withdrew in early November, less than 10 days after the invasion began. In response, Saudi Arabia imposed an embargo on oil shipments to France and the UK, which brought a return to fuel rationing in December 1956.
The aftermath of the Suez Crisis devastated British car sales. Overnight, panicked buyers turned to tiny, German-made "bubblecars," like the Isetta, Messerschmidt, and BMW 600, which were smaller and more frugal than any British-made car.
The crisis alarmed every British automaker, but it was of particular concern to the British Motor Company (BMC), the conglomerate formed from the 1952 merger of Austin Motors and the Nuffield Organisation, which included Morris, MG, Riley, and Wolseley. BMC had controlled a sizable percentage of the British market before Suez and the new German invasion represented a serious threat. Aside from the business implications, BMC chairman Leonard Lord reportedly took personal offense to the bubblecars and was eager to drive them from British shores with a "proper" subcompact car.
BMC's chief engineer at that time was one Alexander Arnold Constantine Issigonis. Born in Smyrna in 1906, Issigonis was a British subject, but he and his mother did not move to England until 1923. Issigonis studied engineering at Battersea Polytechnic, where he famously failed the mathematics exam three times, and subsequently became an engineer at Humber while dabbling in amateur racing. In 1936, he joined Morris as a suspension engineer.
Although Issigonis was still relatively junior in 1943, Morris chief engineer A.V. Oak allowed him to design the company's first postwar car, which emerged in 1948 as the Morris Minor. The Minor was a curious-looking car whose styling was once compared to a poached egg, but it was quite advanced for its time, with unitary construction, independent front suspension via torsion bars, and rack-and-pinion steering. It became one of Morris's most-important products, selling nearly 1.4 million copies between 1948 and 1971.
The success of the Minor won Issigonis great favor with Morris management, who quickly learned that he could do great things if they stayed out of his way. Issigonis was as stubborn as he was iconoclastic and diplomacy was not among his strong suits. He did not suffer fools gladly and had an unapologetic loathing for styling and marketing.
Issigonis briefly left Morris in 1952, following the formation of BMC. Fearing that he would not enjoy the same autonomy under the new, Austin-dominated management, he went to Alvis, where he and Alex Moulton worked on a V8-powered luxury car using Moulton's new Hydrolastic interconnected suspension system. That project was canceled in 1955 and Issigonis accepted Len Lord's invitation to return to BMC as chief engineer.
At the time of the Suez Crisis, Issigonis was working on a new family sedan to replace the Minor. Code-named XC9000, its shape would have been immediately familiar to any later Mini owner, although it was a conventional rear-drive car. In March 1957, Lord asked Issigonis to put the XC9000 on the shelf and develop a new, smaller car to challenge the bubblecars. The new project was code-named XC9003.
TRANSVERSE ENGINE, FRONT-WHEEL DRIVE
By the mid-fifties, BMC had developed a reputation for conservative engineering and product planning. Len Lord had great faith in Issigonis, however, and gave him a free hand for the XC9003 project. The one proviso was that it had to use an existing engine -- BMC did not have the money for both an all-new car and an all-new powerplant. At that, BMC did not have a lot of money, period; even before Suez, its financial condition had been far from robust. The tooling budget for the XC9003 was a modest £10 million, about $28 million at contemporary exchange rates, perhaps $220 million today.
Issigonis did not let the lack of capital dampen his ambitions. His goal for the XC9003 was to provide room for four adults in a car only 10 feet (305 cm) long and four feet (122 cm) wide. Such packaging made a conventional front-engine, rear-wheel-drive (FR) layout impractical; it would require either a front-engine, front-wheel-drive (FF) or rear-engine, rear-wheel-drive (RR) configuration, both of which were uncommon in Great Britain at the time. Citroën, of course, had used front-wheel drive since the mid-thirties, while some German and Italian automakers had opted for RR layouts, but most British manufacturers remained firm adherents of le system Panhard.
BMC did briefly study rear-engine layouts in the late fifties, but Issigonis was convinced that front-wheel drive was the way of the future. The problem was packaging. Most early FWD cars, like the Citroën Traction Avant and the American Cord, had longitudinally mounted engines, with the transmission mounted ahead of the engine -- a bulky arrangement, even with a four-cylinder engine. As a result, while FF cars were more efficient in their use of interior space than FR contemporaries, they were not necessarily any smaller.
Issigonis decided that the solution was to mount the engine transversely, a concept he had studied even before his sojourn at Alvis. A transverse engine would be much shorter than a longitudinal engine, but it presented an additional problem: where to put the transmission. The XC9003 was wide enough to mount the Austin/BMC A-series four between its front wheels, but it was not wide enough for both the engine and transmission. Issigonis considered cutting the A-series engine in half, creating an inline two, but the resulting twin was hopelessly gutless, even for an economy car. He finally resorted to mounting the gearbox in the engine sump, sharing the engine's oil supply. It was a simple solution, albeit a daring one; engines and transmissions have very different oiling requirements and a compromise suits the needs of neither. Nevertheless, this solution reduced the powertrain's total length to a mere 18 inches (460 mm).
The familiar Austin gearbox, a four-speed with an unsynchronized low gear, was far from happy in its new role. The prototypes routinely broke their synchros and there was neither time nor money to redesign the transmission before launch. As a stopgap, Issigonis turned the engine 180 degrees, using spur gears to drive the transmission. The additional gears reduced the load on the synchros, although the gearbox would remain a weak point of the early cars.
The XC9003 was originally slated to use the 948 cc (58 cu. in.) A-series engine, shared with the Morris Minor 1000, but the engine was subsequently de-stroked to 848 cc (52 cu. in.). The smaller displacement reduced output to a modest 34 net horsepower (25 kW), but it provided better fuel economy and better range. The latter was an important consideration, because the little car's fuel tank held only 6.5 U.S. gallons (5.4 Imperial gallons, 24.7 liters).
Every aspect of the XC003 was carefully designed to maximize packaging efficiency. Like the Minor, the new car used unibody construction, although front and rear suspension subframes were added late in the development process to reduce the stresses on the body shell. Inside, the seats were extremely upright, improving legroom without increasing the length of the cabin. Nearly every scrap of usable space was put to good use.
The XC9003 had rack-and-pinion steering and fully independent suspension: SLA in front, trailing arms in back, with no anti-roll bars. The new car was originally supposed to have Alex Moulton's Hydrolastic springs, but the scaled-down Hydrolastic suspension wasn't ready in time, so compact rubber springs were substituted at the last minute. The Hydrolastic system would resurface several years later.
Perhaps the most noteworthy space-saving measure was the 10-inch (254 mm) wheels. Their size allowed the wheelhouses to be kept as small as possible, improving packaging efficiency. They also reduced unsprung weight -- an important consideration in a car whose sprung weight was barely over half a ton (454 kg). At the time, no manufacturer made wheels or tires that small, so Issigonis and Lord persuaded Dunlop to make some. There would later be an entire cottage industry creating wheels and tires for the little car.