The Mazda RX-7 is a sports car by the Japanese automaker Mazda. It was produced from 1978 to 2002. The original RX-7 featured a 1146 cc twin-rotor Wankel rotary engine and a sporty front-midship, rear-wheel drive layout. The RX-7 was a direct replacement for the RX-3 (both were sold in Japan as the Savanna) and subsequently replaced all other Mazda rotary cars with the exception of the Cosmo.
The original RX-7 was a sports car. The compact and lightweight Wankel engine (rotary engine) is situated slightly behind the front axle, a configuration marketed by Mazda as "front mid-engine". It was offered as a two-seat coupé, with optional "occasional" rear seats in Japan, Australia, the United States, and other parts of the world. These rear seats were initially marketed as a dealer-installed option for the North American markets.
The RX-7 made Car and Driver magazine's Ten Best list five times. In total, 811,634 RX-7s were produced.
First generation (SA/FB)
Series 1 (1979–1980) is commonly referred to as the "SA22C" from the first alphanumerics of the vehicle identification number. This series of RX-7 had exposed steel bumpers and a high-mounted indentation-located license plate, called by Werner Buhrer of Road & Track magazine a "Baroque depression."In 1980 Mazda released 3000 special models known as the LS (Leather Sport). This package added an LS badge, full leather upholstery, sunroof, and gold-colored alloys. This model was only available in three different colors Aura White (1250 made), Brilliant Black (1250 made) and Solar Gold (500 made).
The Series 2 (1981–1983) had integrated plastic-covered bumpers, wide black rubber body side moldings, wraparound taillights and updated engine control components. The GSL package provided optional 4-wheel disc brakes, front ventilated (Australian model) and clutch-type rear limited slip differential (LSD). Known as the "FB" in North America after the US Department of Transportation mandated 17 digit Vehicle Identification Number changeover. Elsewhere in the world, the 1981-1985 RX-7 retained the 'SA22C' VIN prefix. As a result, enthusiasts outside North America never picked up the "FB" nickname. The license-plate surround looks much like Buhrer's "Styling Impressions.
The Series 3 (1984–1985) featured an updated lower front fascia. North American models received a different instrument cluster (the NA S3 RX-7 is the only rotary-engined car to not have a centrally mounted tachometer). GSL package was continued into this series, but Mazda introduced the GSL-SE sub-model. The GSL-SE had a fuel injected 1.3 L 13B RE-EGI engine producing 135 hp (101 kW) and 135 lb·ft (183 N·m). GSL-SEs had much the same options as the GSL (clutch-type rear LSD and rear disc brakes), but the brake rotors were larger, allowing Mazda to use the more common lug nuts (versus bolts), and a new bolt pattern of 4x114.3 (4x4.5"). Also, they had upgraded suspension with stiffer springs and shocks. The external oil cooler was reintroduced, after being dropped in the 1983 model-year for the controversial "beehive" water-oil heat exchanger.
1985 - Mazda released in Australia the RX7 Finale - this was the last of the series and brought out in limited numbers. The Finale featured power options and a brass plaque mentioning the number the car was as well as "Last of a legend" on the plaque. The finale had special stickers and a blacked out section between the window & rear hatch.
The handling and acceleration of the car were noted to be of a high caliber for its day. This generation RX-7 had "live axle" 4-link rear suspension with Watt's linkage, a 50/50 weight ratio, and weighed under 2500 lb (1100 kg). It was the lightest generation of RX-7 ever produced. 12A-powered models accelerated from 0–60 mph in 9.2 s, and turned 0.779g (7.64 m/s²) laterally on a skidpad. The 12A engine produced 100 hp (75 kW) at 6000 rpm, allowing the car to reach speeds of over 120 miles per hour (190 km/h). Because of the smoothness inherent in the Wankel rotary engine, little vibration or harshness was experienced at high rpm, so a buzzer was fitted to the tachometer to warn the driver when the 7000 rpm redline was approaching
The 12A engine has a long thin shaped combustion chamber, having a large surface area in relation to its volume. Therefore, combustion is cool, giving few oxides of nitrogen. However, the combustion is also incomplete, so there are large amounts of partly burned hydrocarbons and carbon monoxide. The exhaust is hot enough for combustion of these to continue into the exhaust. An engine driven pump supplies air into the exhaust to complete the burn of these chemicals. This is done in the "thermal reactor" chamber where the exhaust manifold would normally be on a conventional engine. Under certain conditions the pump injects air into the thermal reactor and at other times air is pumped through injectors into the exhaust ports. This fresh air is needed for more efficient and cleaner burning of the air/fuel mixture.
Options and models varied from country to country. The gauge layout and interior styling in the Series 3 was only changed for North American versions. Additionally, North America was the only market to have offered the first generation RX-7 with the fuel injected 13B, model GSL-SE. A turbocharged (but non-intercooled) 12A engine was available for the top-end model of Series 3 in Japan.
Sales were strong, with a total of 474,565 first generation cars produced; 377,878 were sold in the United States alone. In 2004, Sports Car International named this car #7 on its list of Top Sports Cars of the 1970s. In 1983, the RX-7 would appear on Car and Driver magazine's Ten Best list for the first time in 20 years
Second generation (FC)
The Series 4 (1986–1988) was available with a naturally aspirated, fuel-injected 13B-VDEI producing 146 hp (108 kW). An optional turbocharged model, known as the Turbo II in the American market, had 182 hp / 185 ps (135 kW). The Series 5 (1989–1992) featured updated styling and better engine management, as well as lighter rotors and a higher compression ratio, 9.7:1 for the naturally aspirated model, and 9.0:1 for the turbo model. The naturally aspirated Series 5 FC made 160 hp (119 kW), while the Series 5 Turbo made 200 hp / 205 ps (147 kW).
The second generation RX-7 ("FC", VIN begins JM1FC3 or JMZFC1), still known as the Savanna RX-7 in Japan, featured a complete restyling reminiscent of the Porsche 944 or Porsche 924. Mazda's stylists, led by Chief Project Engineer Akio Uchiyama, focused on the Porsche 944 for their inspiration in designing the FC because the new car was being styled primarily for the American market, where the majority of first generation RX-7's had been sold. This strategy was chosen after Uchiyama and others on the design team spent time in the United States studying owners of earlier RX-7's and other sports cars popular in the American market. The Porsche 944 was selling particularly well at the time and provided clues as to what sports-car enthusiasts might find compelling in future RX-7 styling and equipment. While the SA22/FB was a purer sports car, the FC tended toward the softer sport-tourer trends of its day. Handling was much improved, with less of the oversteer tendencies of the FB. The rear end design was vastly improved from the FB's live rear axle to a more modern, Independent Rear Suspension (rear axle). Steering was more precise, with rack and pinion steering replacing the old recirculating ball steering of the FB. Disc brakes also became standard, with some models (S4: GXL, GTU, Turbo II, Convertible; S5: GXL, GTUs, Turbo, Convertible) offering four-piston front brakes. The rear seats were optional in some models of the FC RX-7, but are not commonly found in the American Market. Mazda also introduced Dynamic Tracking Suspension System (DTSS) in the 2nd generation RX-7. The revised independent rear suspension incorporated special toe control hubs which were capable of introducing a limited degree of passive rear steering under cornering loads. The DTSS worked by allowing a slight amount of toe-out under normal driving conditions but induced slight toe-in under heavier cornering loads at around 0.5 G's or more; toe-out in the rear allows for a more responsive rotation of the rear, but toe-in allowed for a more stable rear under heavier cornering. Mazda also introduced Auto Adjusting Suspension (AAS) in the 2nd generation RX-7. The system changed damping characteristics according to the road and driving conditions. The system compensated for camber changes and provided anti-dive and anti-squat effects. The Turbo 2 uses a turbo charger with a twin scroll design. Engineered to cancel the turbo lag at low engine speeds is the smaller primary chamber. At higher revolutions the secondary chamber is opened pumping out 33% more power than the naturally aspirated counterpart. The Turbo 2 also has an air-to-air intercooler that has its own intake on the hood.
Though about 80 lb (36 kg) heavier and more isolated than its predecessor, the FC continued to win accolades from the press. The FC RX-7 was Motor Trend's Import Car of the Year for 1986, and the Turbo II was on Car and Driver magazine's Ten Best list for a second time in 1987.
In the Japanese market, only the turbo engine was available; the naturally-aspirated version was allowed only as an export. This can be attributed to insurance companies penalizing turbo cars (thus restricting potential sales). This emphasis on containing horsepower and placating insurance companies to make RX-7's more affordable seems ironic in retrospect. Shortly after the discontinuance of the second generation RX-7's in 1992, an outright horsepower "arms race" broke out between sports car manufacturers, with higher and higher levels of power required to meet buyer demands. This rising horsepower phenomena arose from the US CAFE standards remaining stable while engine technologies marched forward rapidly.
Mazda sold 86,000 RX-7's in the US alone in 1986, its first model year, with sales peaking in 1988.
Australian Motors Mazda released a limited run of 250 'Sports' model Series 4 RX-7's; each with no power steering, power windows or rear wiper as an attempt to reduce the weight of the car. In Japan, there was a special limited release of the FC called Infini with only 600 made for each year. Some special noted features for all Infini series are: infini logo on the back, upgraded suspension, upgraded ECU, higher horsepower, lightened weight, 15" BBS aluminum alloy wheels, Infini logo steering wheel, aero bumper kits, bronze colored window glass, floor bar on the passenger side, aluminum bonnet with scoop, flare and holder. The car was thought as the pinnacle of the RX-7 series (until the FD came out). The Infini IV came with other special items such as black bucket seats, 16" BBS wheels, Knee pads, and all the other items mentioned before. There are differing years for the Infini, which noted the series. Series I was introduced in 1987, Series II was introduced in 1988, Series III was introduced in 1990, and Series IV was introduced in 1991. Series I and II came in White or Black, Series III came in Forest Green only, and Series IV came in Forest Green or Noble Green. There are only minor differences between the series, the biggest change which was from the Series II being an S4 (1986–1988) and the Series III and IV being an S5 (1989–1991).
Third generation (FD)
The third generation of the RX-7, FD (with FD3S for the JDM and JM1FD for the USA VIN), featured an updated body design. The 13B-REW was the first-ever mass-produced sequential twin-turbocharger system to export from Japan, boosting power to 255 PS (188 kW; 252 hp) in 1993 and finally 280 PS (206 kW; 276 hp) by the time production ended in Japan in 2002.
- Series 6 (1992–1995) was exported throughout the world and had the highest sales. In Japan, Mazda sold the RX-7 through its Efini brand as the Efini RX-7. Models in Japan included the Type R, the top-of-the-range Type RZ, the Type RB, the A-spec and the Touring X, which only came with a 4-speed automatic reducing power to 255 PS (188 kW; 252 hp), but the others ran on the standard 265 PS (195 kW; 261 hp) engine with a 5-speed manual gearbox. Only the 1993–1995 model years were sold in the U.S. and Canada. Series 6 came with 255 PS (188 kW; 252 hp) and 294 N·m (217 ft·lbf). In the UK only 124 examples of this model were sold through the official Mazda network, Only one spec. was available and this included twin oil-coolers, electric sunroof, cruise control and the rear storage bins in place of the back seats.
- In North America, three models were offered; the "base", the touring, and the R models. The touring FD had a sunroof, leather seats, and a complex Bose Acoustic Wave system. The R (R1 in 1993 and R2 in 1994–95) models featured stiffer suspensions, an aerodynamics package, suede seats, and Z-rated tires.
- There is also a "Touring Model" which includes a sun roof, and Bose stereo system. Compared to the R1 and R2 which both don't have a moon roof, and they have an extra front oil cooler in the front bumper, and other race modification equipment
- Series 7 (1996–1998) included minor changes to the car. Updates included a simplified vacuum routing manifold and a 16-bit ECU allowing for increased boost which netted an extra 10 PS (7 kW). In Japan, the Series 7 RX-7 was marketed under the Mazda brand name. The Series 7 was also sold in Australia, New Zealand and the UK. Series 7 RX-7s were produced only in right-hand-drive configuration.
- Series 8 (January 1999– August 2002) was the final series, and was only available in the Japanese market. More efficient turbochargers were installed, while improved intercooling and radiator cooling was made possible by a revised frontal area. The seats, steering wheel, and front and rear lights were all changed. The rear spoiler was modified and gained adjustability. The top-of-the-line "Type RS" came equipped with a Bilstein suspension and 17" wheels as standard equipment, and reduced weight to 1,280 kg (2,822 lb). Power was 280 PS (206 kW; 276 hp) with 313.8 N·m (231 ft·lbf) of torque as per the maximum Japanese limit. The very limited edition Type RZ version included all the features of the Type RS, but at a lighter weight (at 1270 kg). It also featured custom gun-metal colored BBS wheels and a custom red racing themed interior. Further upgrades included a new 16-bit ECU and ABS system upgrades. The improved ABS system worked by braking differently on each wheel, allowing the car better turning during braking. The effective result made for safer driving for the average buyer. Easily the most collectible of all the RX-7s was the last 1,500 run-out specials. Dubbed the "Spirit R", they combined all the "extra" features Mazda had used on previous limited-run specials plus new exclusive features. They still command amazing prices on the Japanese used car scene years later. Sticker prices when new were 3,998,000 yen for Type-A and B and 3,398,000 yen for Type-C. Mazda's press release said "The Type-A Spirit R model is the ultimate RX-7, boasting the most outstanding driving performance in its history."
The FD RX-7 was Motor Trend's Import\Domestic Car of the Year. When Playboy magazine first reviewed the FD RX-7 in 1993, they tested it in the same issue as the [then] new Dodge Viper. In that issue, Playboy declared the RX-7 to be the better of the two cars. It went on to win Playboy's Car of the Year for 1993. The FD RX-7 also made Car and Driver magazine's Ten Best list for 1993 through 1995, for every year in which it was sold state-side. June, 2007 Road&Track magazine proclaimed "The ace in Mazda's sleeve is the RX-7, a car once touted as the purest, most exhilarating sports car in the world.
The sequential twin turbocharged system was a very complex piece of engineering, developed with the aid of Hitachi and previously used on the domestic Cosmo series (JC Cosmo=90–95). The system was composed of two small turbochargers, one to provide torque at low RPM. The 2nd unit was on standby until the upper half of the rpm range during full throttle acceleration. The first turbocharger provided 10 psi (0.7 bar) of boost from 1800 rpm, and the 2nd turbocharger was activated at 4000 rpm and also provided 10 psi. The changeover process, between 3500 rpm and 4000 rpm, provided 8 psi (0.6 bar), was smooth, and provided linear acceleration and a wide torque curve throughout the entire rev range.
Handling in the FD was regarded as world-class, and it is still regarded as being one of the finest handling and best balanced cars of all time. The continued use of the front-midship engine and drivetrain layout, combined with an 50:50 front-rear weight distribution ratio and low center of gravity made the FD a very competent car at the limits.
In the United Kingdom, for 1992, customers were offered only one version of the FD which was based on a combination of the US touring and base model. For the following year, in a bid to speed up sales, Mazda reduced the price of the RX-7 to £25,000, down from £32,000 and refunded the difference to those who bought the car before that was announced. The FD continued to be imported to the UK until 1996. In 1998, for a car that had suffered from slow sales when it was officially sold, with as surge of interest following its appearances in videogames, notably Gran Turismo and the benefit of a newly introduced SVA scheme, which meant an influx of inexpensive Japanese imported cars, the FD would become so popular that there were more parallel and grey imported models brought into the country than Mazda UK had ever imported.
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