MGА моделінің тарихы және ерекшеліктері

The MGA design dates back to 1951, when MG designer Syd Enever created a streamlined body for George Philips' TD Le Mans car. The new bodywork traded the MG TF's articulated fenders and running board for ponton styling, with a single styled envelope fully enclosing the width and uninterrupted length of a car. The TF featured a high driver seating position. A new chassis was designed with the side members further apart and the floor attached to the bottom rather than the top of the frame sections. A prototype was built and shown to the BMC chairman Leonard Lord. He turned down the idea of producing the new car as he had just signed a deal with Donald Healey to produce Austin Healey cars two weeks before. Falling sales of the traditional MG models caused a change of heart, and the car, initially to be called the UA series, was brought back. As it was so different from the older MG models it was called the MGA, the "first of a new line" to quote the contemporary advertising. Rather than the originally intended XPAG unit, the car was fitted with the new straight 4 "BMC B series" engine from the MG Magnette saloon, coupled to a four speed gearbox. Unlike the coupe, the convertible had no exterior door handles. It was a body on frame design, and suspension was independent with coil springs and wishbones at the front and a rigid axle with semi elliptic springs at the rear. Steering was by rack and pinion. The car was available with either wire spoked or steel disc road wheels. While the make (or marque) is MG, the model was named MGA by John Thornley in 1954.

The 1489 cc engine fitted with twin H4 type SU Carburettors produced 68 hp (51 kW) at first, but was soon uprated to 72 hp (54 kW). Lockheed hydraulic drum brakes were used on all wheels. A coupé version was also produced, bringing the total production of standard MGAs to 58,750. An early open car tested by British magazine The Motor in 1955 had a top speed of and could accelerate from 0– in 16.0 seconds. A fuel consumption of was recorded. The test car cost £844 including taxes.

A high performance Twin Cam model was added for 1958. It used a high compression (9.9:1 later 8.3:1) DOHC aluminium cylinder head version of the B Series engine producing Four wheel disc brakes by Dunlop were fitted, along with Dunlop peg drive knock off steel wheels similar to wheels used on racing Jaguars, unique to the Twin Cam and "DeLuxe" MGA 1600 and 1600 MkII roadsters. These wheels and chassis upgrades were used on a small number of the "DeLuxe" models built after Twin Cam production came to a halt. Aside from the wheels, the only outside identifier was a "Twin Cam" logo near the vent aside the bonnet. The temperamental engine was notorious for warranty problems during the course of production, and sales dropped quickly. The engine suffered from detonation and burnt oil. but by then the reputation had been tarnished. Oddly, an open MGA Twin Cam (index PMO 326), road tested by The Autocar magazine in its 18 July 1958 edition only recorded a 0 60 time of 13.3secs with the standing quarter mile of 18.6secs. The mean maximum speed was 113.5 mph, with a best of 114.0 mph.

In May 1959 the standard cars also received an updated engine, now at 1588 cc producing At the front disc brakes were fitted, but drums remained in the rear. 31,501 were produced in less than three years.

The engine size was increased again to 1622 cc by increasing the bore from to for the 1961 Mark II MGA. The cylinder head was also revised with larger valves and re engineered combustion chambers. Horsepower increased to 90 bhp. It also had a higher ratio 4:1 rear axle, which made for more relaxed high speed driving. An inset grille and Morris Mini tail lamps appearing horizontally below the deck lid were the most obvious visual changes. 8,198 Mark II roadsters and 521 coupés were built. Road & Track magazine reviewed the MG A 1600 Mark II in the September 1961 issue and reported an estimated top speed of 105 mph and a 0 60 mph acceleration of 12.8 seconds. As with the 1600 De Luxe, there were also some Mark II De Luxe versions; 290 roadsters and 23 coupés were produced.

The MGA's bodywork was based largely on that of a one off MG TD specially built by the MG factory at the request of racing privateer George Phillips for the 1951 24 Hours of Le Mans. Later, a new chassis was designed so as to seat the driver lower in the car with even cleaner bodywork resulting in the EX 175 prototype. The later MG prototype EX 182 was very close to the final production MGA and was the car actually raced at Le Mans in 1955. Three MGA prototypes were entered in the 1955 24 Hours of Le Mans. Two of the cars finished the race placing 12th and 17th overall, proving the worth of the new car. The third car crashed with serious injuries to the driver, Dick Jacobs. The MGA has been raced extensively in the U. S. since its 1955 introduction and with considerable success. In Sports Car Club of America competition the MGA has won numerous regional and national championships. It has also been a favourite choice of those competing in vintage racing. Kent Prather has been the most successful American MGA driver to date with G Production wins at the SCCA national championships in 1986, 1990, 1995, 2002, 2003, and 2005. Prather and his MGA accomplished this despite the fact that his MGA was often the oldest vehicle competing among several hundred race cars at the SCCA Runoffs. In the United States, the MGA was used in NASCAR from 1960 to 1963 in the Grand National Series, failing to win a single race. After production ended of the MGA, MG (which at that point was the last foreign automaker in NASCAR) decided not to field another entry in the circuit, which resulted in a de facto oligopoly of the NASCAR circuit by Detroit's Big Three. Aside from a brief period in the 1970s when American Motors fielded the AMC Matador in NASCAR competition, not another non Detroit automaker—let alone a non American automaker—would enter NASCAR until 2007, when Toyota entered NASCAR competition with the Camry.