Mazda MX-5
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According to a 2003 Edmunds.com article, "the Miata deserves credit not only for reviving a dormant passion for roadsters, but for emboldening other manufacturers."
Generations and overview
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 — 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.The MX-5 was conceived as an elemental 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 a (detachable) rear subframe. 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. Many 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 120 bhp (89 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.
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 over 150 awards in its history, including making Car and Driver magazine's annual Ten Best list seven times; 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.
From idea to production
In 1976, Bob Hall, a journalist at Motor Trend magazine who was an expert in Japanese cars and fluent in the language, met Kenichi Yamamoto, head of Research and Development at Mazda. Yamamoto asked Hall what kind of car Mazda should make in the future:The California team proposed a front-engine, rear-wheel drive layout, codenamed Duo 101, in line with the British roadster ancestry, but their Japanese counterparts favored the more common front-engine, front-wheel drive layout or the rear mid-engine, rear-wheel drive layout.
The first round of judging the competing designs was held in April 1984. At this stage, designs were presented solely on paper. The mid-engined car appeared the most impressive, although it was known at the time that such a layout would struggle to meet the noise, vibration and harshness (NVH) requirements of the project. It was only at the second round of the competition in August 1984, when full-scale clay models were presented, that the Duo 101 won the competition and was selected as the basis for Mazda's new light-weight sports car.
The Duo 101, so named as either a soft top or hard top could be used, incorporated many key stylistic cues inspired by the Lotus Elan, a 1960s roadster. International Automotive Design (IAD) in Worthing, England was commissioned to develop a running prototype, codenamed V705. It was built with a fiberglass body, a 1.4 L (85 cu in) engine from a Mazda Familia and components from a variety of early Mazda models. The V705 was completed in August 1985 and taken to the U.S.A. where it rolled on the roads around Santa Barbara and got positive reactions.
The project received final approval on 18 January 1986. The model's codename was changed to P729 as it moved into production phase, under head of program Toshihiko Hirai. The task of constructing five engineering mules (more developed prototypes) was again allocated to IAD, which also conducted the first front and rear crash tests on the P729. While Tom Matano and Koichi Hayashi worked on the final design, the project was moved to Japan for engineering and production details.
By 1989, with a definitive model name now chosen, the MX-5 (as in "Mazda eXperimental", project number 5) was ready to be introduced to the world as a true lightweight sports car, weighing just 940 kg (2,100 lb).
Jinba ittai
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)."Referring to the design of the third generation, Mazda MX-5 program manager (NA), Takao Kijima said:
| “ | Jinba Ittai drove all of the development team's decisions, yielding a car so nimble and fun to drive that the driver and car achieve true unity. This unified rider and horse concept allowed us to create a new MX-5 that's true to the spirit of the original, exceptionally lightweight, and lots of fun to drive. | ” |
- 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 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.
First generation (NA)
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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. 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. 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 original MX-5 came with a 1.6 L (98 cu in) double overhead cam inline four-cylinder engine, producing 90 kW (120 bhp) and 136 N·m (100 ft·lbf) of torque. The engine employs an electronic fuel injection system using a vane-type air flow meter and a camshaft angle sensor instead of a distributor.[6] This engine, codename B61P, had been previously used in the 323 series. Standard transmission was 5-speed manual. Japan and the USA got an optional automatic transmission which proved unpopular; these markets also received an optional viscous limited slip rear differential, although were only available for cars with a manual transmission.
The NA could reach 60 mph (97 km/h) in 9.4 seconds and had a top speed of 190 km/h (120 mph). This first generation of Miata (often referred to as the M1) included a special edition in 1991, produced in British Racing Green with the first use of tan interior.
1500 LE (Limited Edition)cars were produced in 1993. This model featured red leather interior, upgraded stereo, Nardi shift knob, leather wrapped steering wheel, cruise, limited slip differential, power windows, power mirrors, power steering, air conditioning, BBS wheels, Bilstein shocks, front and rear spoilers, ABS brakes, stainless sill plates and Harley style peanut tank door speaker trim. All '93 LE cars came in black.
For the 1994 model year, the first-generation MX-5 was freshened with the introduction of the more powerful 1.8 L (110 cu in) BP-ZE engine, dual airbags and a limited slip differential in some markets. The chassis was substantially braced to meet new side-impact standards, most visibly by adding a "track bar" between the seatbelt towers inside the car, but also to the front and rear subframes. Also, 1994 and 1995 were the only years in which Mazda offered a light metallic blue paint (Laguna Blue Mica), making these cars rare collectors cars to some. 1994 also saw the introduction of the "R" package, a sport-themed package with Bilstein shocks and subtle underbody spoilers, in addition to the removal of unnecessary items such as power steering. No body style changes were made, though.
The new 1.8 L (110 cu in) engine produced 98 kW (131 bhp), which was then increased by 1 kW (1.3 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 first generation MX-5 was phased out with the 1997 model year (with the exception of 400 limited edition Berkeley models sold only in the UK in 1998 to mark the end of the NA), with the final 1500 NAs produced for the US market being the "STO" ("Special Touring Option") versions.
Second generation (NB)
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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 exactly 1,000 kg (2,200 lb). The new generation was slightly more aerodynamic than the original, with a Cd figure of 0.36.
The NB continued to employ four-wheel independent suspension, with enlarged anti-roll bars at the front and rear, but the wheels, tires and brakes were significantly upgraded: anti-lock braking system was offered as an option; alloy wheels were now 14 in (360 mm) or 15 in (380 mm) in diameter and 6 in (150 mm) in width, depending on the trim package; sports models were equipped with the larger wheels and 195/50VR15 tires.
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 ft·lbf (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 7.9 s and had a top speed of 197 km/h (122 mph).
In 1999, Mazda celebrated the 10th anniversary of the MX-5 with the 10th Anniversary Model, a limited edition featuring some until-then exclusive features, namely a six-speed transmission and Bilstein shock absorbers; performance figures were slightly different, with faster acceleration but lower top speed than the standard 1.8 L (110 cu in) NB.
For the 2001 model year, a facelift to the second-generation MX-5 was released. There were some minor exterior changes, with a press-release of July 18, 2000 announcing the changes as "resulting in an even sportier and more forceful look". Some cockpit elements were changed, with the instrument panel gauges receiving a white face and red numbers. The seats were also upgraded, incorporating more support in the side bolsters and taller headrests. Added for top models were 16-inch wheels with 205/45VR16 low-profile tires and larger brakes at the front and rear. The upgraded tires and suspension allowed the new model to pull 0.88 g in lateral grip in tests by Car and Driver magazine. The body was strengthened, gaining 16% in bending rigidity and 22% in torsional rigidity. With the minimum of options, the 2001 model weighed 1,065 kg (2,350 lb).
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 117 kW (157 bhp) (Japan and Australia) or 110 kW (150 bhp) (US and Europe). 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.
In 2003 Mazda launched a campaign to target a younger group of drivers with the introduction of the Shinsen Version (SV) Miata. The Shinsen (Japanese for "Fresh and New,") provided an intermediate step between the base model and the pricier LS. Equipped with most standard features on the LS, such as cruise control and aluminum brush trim, the SV added a touch of comfort and style without a hefty price tag. This limited production model also shared an inverted color scheme of the same year Special Edition. With a titanium silver exterior, dark blue top and interior, the Shinsen Version was a handsome addition to the Miata family.
Third generation (NC)
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| Production | 2006-Present |
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| Body style(s) | 2-door roadster 2-door hardtop |
| Engine(s) | 1.8 L (110 cu in) MZR I4 (Europe) 2.0 L (120 cu in) MZR I4 |
| Transmission(s) | 5-speed manual 6-speed automatic 6-speed manual |
| Wheelbase | 91.7 in (2,330 mm) |
| Length | 157.3 in (4,000 mm) |
| Width | 67.7 in (1,720 mm) |
| Height | 49.0 in (1,240 mm) PRHT: 49.4 in (1,250 mm) |
| Curb weight | 1,095 kg (2,410 lb) |
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 166 bhp (124 kW) and 140 ft·lbf (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 ft·lbf) 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 160 bhp (120 kW) and 188 N·m (139 ft·lbf), 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 ft·lbf), 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. 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)).
The NC was launched with a special edition called "3rd Generation Limited" which featured added chrome accents and special wheels. 3500 were built worldwide (300 in the UK, 750 in the USA), delivered in advance of standard models.
The NC offers a wider range of accessories for customization than the earlier generations. The softtop, in cloth instead of vinyl, can now be chosen in more than two colors: black and cream as previously, but also grey, camel, blue and green; and the interior can be customized to the exterior paint color.
For 2008, Mazda released a Special Edition MX-5 in Icy Blue exterior, with exclusive 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, grille surround and fog lamp surround. The 2008 Special Edition was limited to 750 units in the US.
Facelift
The 2009 MX-5 facelift debuted at the 2008 Paris Auto Show. Major changes concern the restyled front which now incorporates elements from Mazda’s newer models like the larger grille and new head- and fog lights. Further restyled elements are the side skirts, rear bumper and the tail lights. The hardtop Roadster Coupe now features a mesh grille bordered by a chrome frame and chrome elements inside the headlamps and outer door handles.The instrument panel gained darker and features redesigned graphics for the gauges. To create more leg space in the cabin, a protrusion from the door pockets was eliminated.
The 118 kW 2.0-liter engine was upgraded to allow for a 500 rpm higher rev limit and features an improved, sportier sound. The suspension and gearbox have been fine-tuned; latter offers smoother shifts and automatic transmission will be introduced in Europe for the first time.
Safety
In the 2002 Euro NCAP Safety Ratings, the MX5 manufactured in 2002 received 4 out of 5 stars.Production numbers and details
| Year | Production | Sales (U.S.) | Sales (Global) |
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| 1988 | 12 (pre-production cars) | ||
| 1989 | 45,266 | 23,052 | 35,807 |
| 1990 | 95,640 | 35,944 | 75,789 |
| 1991 | 63,434 | 31,240 | 71,586 |
| 1992 | 52,712 | 24,964 | 53,031 |
| 1993 | 44,740 | 21,588 | 45,155 |
| 1994 | 39,623 | 21,400 | 38,826 |
| 1995 | 31,886 | 20,174 | 35,673 |
| 1996 | 33,610 | 18,408 | 33,205 |
| 1997 | 27,037 | 17,218 | 32,035 |
| 1998 | 58,682 | 19,845 | 49,205 |
| 1999 | 44,851 | 17,738 | 46,370 |
| 2000 | 47,496 | 18,299 | 44,573 |
| 2001 | 38,870 | 16,486 | 39,258 |
| 2002 | 40,754 | 14,392 | 38,917 |
| 2003 | 30,106 | 10,920 | 32,990 |
| 2004 | 24,232 | 9,356 | 26,531 |
| 2005 | 29,950 | 9,801 | 14,316 |
| 2006 | 48,389 | 16,897 | 22,546 |
| Total | 797,293 | 347,722 | 735,813 |
The 250,000th MX-5 rolled out of the factory on November 9, 1992; the 500,000th, in February 8, 1999; the 750,000th, in March 2004; and the 800,000th in January 2007.
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