Friday, July 8, 2011

Mazda MX-5

The Mazda MX-5, also known as Miata (pronounced /miˈɑːtə/) in North America and Roadster in Japan, is a lightweight two-seater roadster, of front engine, rear wheel drive configuration, built by Mazda in Hiroshima, Japan. The model was introduced in 1989 and continues to be a best selling convertible. There are currently three generations of MX-5, with the current (NC) model having been in production since 2006. Now in its third generation, the MX5's first generation, the NA, sold over 400,000 units from 1989 to 1997 – with a 1.6 L (98 cu in) straight-4 engine to 1993, a 1.8 L (110 cu in) engine thereafter (with a de-tuned 1.6 as a budget option in some markets) – recognizable by its pop-up headlights. The second generation (NB) was introduced in 1998 with a slight increase in engine power; it can be recognized by the fixed headlights and the glass rear window. The third generation (NC) was introduced in 2005 with a 2.0 L (120 cu in) engine. It was launched at a time when production of small roadsters had fallen into almost total disuse. The Alfa Romeo Spider was the only comparable volume model in production at the time of the MX-5's launch. Just a decade earlier, a whole host of similar models - notably the MG B, Triumph TR7, Triumph Spitfire and Fiat Spider - had been available. The MX-5 was conceived as a small roadster – with light weight and minimal mechanical complexity limited only by legal and safety requirements; technologically modern, but a philosophically direct descendant of the small British roadsters of the 1960s such as the Triumph Spitfire, Austin-Healey Sprite, MG Midget and Lotus Elan. The MX-5 was designed with a traditional front-engine, rear-wheel drive layout and four-wheel independent double wishbone suspension. It has a longitudinally-mounted four cylinder engine coupled to a manual transmission (5 speed for NA, 5 or 6 speed in NB & NC); an automatic transmission is a cost option. The body is a conventional, but light, unibody or monocoque construction, with (detachable) front and rear subframes. The MX-5 also incorporates a truss marketed as the Powerplant Frame (PPF) which connects the engine to the differential, minimizing flex and contributing to responsive handling. Some MX-5s feature limited slip differentials and anti-lock braking system. Traction control is an option available on NC models. The earlier cars weighed in at just over a ton, with engine power output usually 116 bhp (87 kW). The later cars were heavier, with higher power engines. With an approximate 50:50 front/rear weight balance, the car has nearly neutral handling. Inducing oversteer is easy and very controllable, thus making the MX-5 a popular choice for amateur and stock racing, including, in the USA, the Sports Car Club of America's Solo2 autocross and Spec Miata race series and in the UK the Ma5da racing championship. Beginning with the third generation, Mazda consolidated worldwide marketing using the MX-5 name, though enthusiasts in the USA still refer to it as Miata, a name that means "reward" in Old High German. The MX-5 has won many awards including Wheels Magazine 's Car of the Year for 1989 and 2005; Sports Car International's "best sports car of the 1990s" and "ten best sports cars of all time"; 2005-2006 Car of the Year Japan; and 2005 Australian Car of the Year - and making Car and Driver magazine's annual Ten Best list 10 times.

The design credo Mazda has used across the three generations of the MX5's development was the phrase Jinba ittai (人馬一体?, [dʑimba itːai]), which translates loosely into English as "rider (jin) horse (ba) as one (ittai)". With the first generation of the Miata, the phrase was developed into five specific core design requirements: That the car would be as compact and as light as possible while meeting global safety requirements. That the cockpit would comfortably accommodate two full-stature[clarification needed] occupants with no wasted space. That the basic layout would continue with the original's front-midship rear-drive configuration with the engine positioned ahead of the driver but behind the front axle for 50:50 weight distribution. That all four wheels would be attached by wishbone or multi-link suspension systems to maximize tire performance, road grip, and dynamic stability. And that a power-plant frame would again provide a solid connection between the engine and rear-mounted differential to sharpen throttle response. The MX-5 was unveiled at the Chicago Auto Show on February 10, 1989, with a price tag of US$14,000 (US$24,100 in 2008 adjusted for inflation).[citation needed] The MX-5, with production code NA, was made available for delivery to buyers worldwide in the following dates: March 1989 in Japan; May 1989 (as a 1990 model) in the USA and Canada; and 1990 in Europe. An optional hardtop was made available at the same time, in sheet moulding compound (SMC). Demand initially outstripped production, fueled by enthusiastic press reviews. In Japan, the car was not badged as a Mazda, as the company was experimenting with the creation of different marques for deluxe models, similar to Nissan's Infiniti and Toyota's Lexus (both brands of which launched at the same time as the Miata). Instead, the Mazda MX-5 was sold as the Eunos Roadster in that market. The body shell of the NA was all-steel with a light-weight aluminium hood. Overall dimensions were 3,970 mm (156 in) in length, 1,675 mm (65.9 in) in width, and 1,235 mm (48.6 in) in height. Without options, the NA weighed only 2150 lb. Drag coefficient was indicated as 0.38. Suspension was an independent double wishbone on all four wheels, with an anti-roll bar at the front and rear. Four wheel-disc brakes, ventilated at the front, were behind alloy wheels with 185/60HR14 radial tires. The base model came with stamped steel wheels from the then-current 323/Protege. The original MX-5 came with a 1.6 L (98 cu in) dual overhead cam inline four-cylinder engine, producing 86 kW (115 bhp) at 6,800 rpm, and 136 N·m (100 lbf·ft) of torque at 5,500 rpm. The engine employs an electronic fuel injection system using a vane-type air flow meter and an electronic ignition system with a camshaft angle sensor instead of a distributor. This engine, codename B6ZE(RS), was specifically designed for the MX-5 and featured a lightened crankshaft, flywheel, and aluminum sump with cooling fins. Standard transmission was 5-speed manual. In Japan and the USA, an optional automatic transmission was also offered but proved to be unpopular. The Japanese and American markets also received an optional viscous limited slip rear differential, although it was only available for cars with a manual transmission. To achieve the low introductory price, the base model was stripped. It had steel wheels, manual steering, roll-up windows, and no stereo or air-conditioning. Power steering, air-conditioning, and stereo were added as standard equipment in later years. The NA could reach 60 mph (97 km/h) in 7.9 seconds and had a top speed of 209|km/h|130 mph. This first generation of Miata (often referred to as the NA) included a special edition in 1991, produced in British Racing Green with the first use of tan interior. The new 1.8 L (110 cu in) engine produced 98 kW (131 bhp), which was then increased to 99 kW (133 bhp) for the 1996 model year. The base weight increased to 990 kg (2,200 lb). Performance was improved slightly, the additional power being partly offset by the extra weight. In some markets such as Europe, the 1.6 L (98 cu in) engine continued to be available as a lower-cost option, but was detuned to 66 kW (89 bhp). This lower-powered model did not receive all the additional chassis bracing of the new 1.8 L (110 cu in). Japanese and US cars were fitted with an optional Torsen LSD, which was far more durable than the previous viscous differential.



The New Mazda MX-5


In 1998, Mazda released the second-generation MX-5, production code NB, for the 1999 model year. The NB featured a more powerful engine and external styling cues borrowed from the third generation Mazda RX-7 model. Prices in the United States, the main market for the MX-5, started at US$19,770 (US$26,300 in 2008 adjusted for inflation). Although many parts of the interior and body were different, the most notable changes were the headlights: the first generation's retractable headlights no longer passed pedestrian safety tests and were replaced by fixed ones. The new car grew slightly in width compared to the earlier model; its dimensions were: length 3,945 mm (155.3 in), width 1,678 mm (66.1 in), height 1,228 mm (48.3 in) and wheelbase 2,265 mm (89.2 in). Without options, the NB weighed 1000|kg 2300 lb. The new generation was slightly more aerodynamic than the original, with a Cd figure of 0.36. The BP-4W engine remained at 1.8 L (110 cu in) but received several minor updates. The engine compression ratio was raised from 9.0:1 to 9.5:1 by adding slightly domed pistons; the intake cam was changed to a solid lifter design with a stronger cam; the intake runners in the head were straightened and the intake manifold was mounted higher up. Mazda's Variable Intake Control System was introduced, which effectively gave a long narrow intake manifold at low rpm for better swirl, changing to a short, free-flowing manifold at high rpm for maximum breathing. Power output of the new engine was quoted at 106 kW (142 bhp) with 116 lbf·ft (157 N·m) of torque. The 1.6 L (98 cu in) B6 engine remained available in Europe and Japan. The base-model 1.8 L (110 cu in) NB could reach 60 mph (97 km/h) in 7.5 s and had a top speed of 130 mph (210 km/h). The 1.8 L (110 cu in) BP-Z3 engine was slightly modified and now featured variable valve timing on the intake camshaft. The intake and exhaust system also received a minor upgrade. These modifications resulted in a power output of 107 kW (143 bhp) (Japan and Australia) or 100 kW (130 bhp) (US only). In the United States, Mazda erroneously quoted the power figure for the Japanese and Australian model in early catalogues. Car and Driver magazine and numerous owners confirmed the missing power, and Mazda offered to buy back the 2001 cars due to those misleading power claims. Owners who did not take up the buy back offer were offered an apology and free servicing for the warranty period.


Production of the third-generation MX-5, code NC, began May 17, 2005, for delivery in August, for the 2006 model year. This was partially due to the declining sales of the MX-5 during its second generation run. The exterior styling resembles the original design, but unlike the update from NA to NB, which was mostly a nose/tail/interior change, the NC shares no components with the NB, except for the side-panel turning-lights on non-USA models. The suspension has changed from a 4-wheel double wishbone setup to a front wishbone/rear multilink setup. Technologies like traction control and stability control were added to increase driveability. For the USA, the engine is the new 16-valve, 2.0 L (120 cu in) MZR I4, producing 170 bhp (130 kW) and 140 lbf·ft (190 N·m) coupled to either a 5-speed or a 6-speed manual transmission or 158 bhp (118 kW) with the optional 6-speed automatic transmission. A limited slip differential is available with the 6-speed option. In Australia the 2.0 L (120 cu in) MZR is offered, rated at 118 kW (158 bhp) and 188 N·m (139 lbf·ft) and the 6-speed transmission and LSD are standard. In Europe, two engines are offered: the 2.0 L (120 cu in) MZR rated at 158 bhp (118 kW) and 188 N·m (139 lbf·ft), coupled to the 6-speed manual transmission; and a new 1.8 L (110 cu in) MZR, rated at 126 bhp (94 kW) and 167 N·m (123 lbf·ft), coupled to the 5-speed manual transmission. A six-speed automatic transmission, with steering wheel mounted paddle shifters, is optional. A test by Car and Driver magazine revealed a 0-60 mph (97 km/h) time of 6.5 s for the 2.0 L (120 cu in) U.S.-spec NC.[10] Manufacturer figures for the European-spec model are: 0-100 km/h (62 mph) in 9.4 s (1.8 L (110 cu in)) and 7.9 s (2.0 L (120 cu in)). In July 2006, Mazda unveiled a coupé convertible version of the NC with a three-piece folding hardtop, named "MX-5 Roadster Coupe" in Europe, "Roadster Power Retractable Hard Top" in Japan, and "MX-5 Miata Power Retractable Hard Top" in Canada and the USA. Adding 36 kg (79 lb) to the weight of a comparable model with soft top, the hard top takes 12 seconds to raise or lower and it does not take any of the existing trunk space when folded down. The first units were delivered to customers in late August, for a price premium less than the cost of a separate hard top. Performance times are slightly affected with the weight increase, to 9.6 s (1.8 L (110 cu in)) and 8.2 s (2.0 L (120 cu in)) from 0-100 km/h (62 mph), but top speed is increased from 196 km/h (121.8 mph) to 200 km/h (124.3 mph) (1.8 L (110 cu in)) and from 210 km/h (130 mph) to 215 km/h (134 mph) (2.0 L (120 cu in)), for the European-spec model. For 2008, Mazda released a Special Edition MX-5 in Icy Blue exterior, with exclusive Dark Saddle Brown folding top, with matching leather with blue stitching steering wheel, seats, and hand brake. The Special Edition also featured a silver-accented shift knob, dark-silver finished instrument panel with chrome accents, special 17 in (430 mm) alloy wheels, stainless steel MX-5 scuff plate, and chrome front headlight bezel, as well as grille and fog lamp surrounds. The 2008 Special Edition was limited to 105 PRHT-equipped units in Canada and 750 soft-top units in the US.

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