The Mazda RX-7 is a sports car which was manufactured and marketed by Mazda from 1978 to 2002 across three generations. It has a front mid engine, rear-wheel-drive layout and uses a compact and lightweight Wankel rotary engine.
The first-generation RX-7, codenamed SA (early) and FB (late), is a two-seater coupé with a rear hatchback. It featured a 12A carbureted rotary engine as well as the option for a 13B rotary engine with electronic fuel injection in later years. The second-generation RX-7, carrying the internal model code FC, was offered as a two-seater coupé with a 2+2 option available in some markets, as well as in a convertible body style. This was powered by the 13B rotary engine, offered in naturally aspirated or turbocharged forms. The third-generation RX-7, model code FD, was offered as a two-seater coupé with a 2+2 version offered as an option for the Japanese market. It featured a sequentially turbocharged 13B REW engine.
More than 800,000 RX-7s were manufactured over its lifetime.
Series 1 (1978–1980)
Series 1 (produced from 1978 until 1980) is commonly referred to as the "SA22C" from the first alphanumeric of the vehicle identification number. Mazda's internal project number for what was to become the RX-7 was X605. In Japan, it was introduced in March 1978, replacing the Savanna RX-3, and joined Mazda's only other remaining rotary engine-powered products, called the Cosmo, which was a two-door luxury coupé, and the Luce luxury saloon.
The lead designer at Mazda was , whose son, , would go on to design the Mazda Demio and the RX-7's successor, the RX-8. The transition of the Savanna to a sports car appearance reflected products from other Japanese manufacturers. The advantage the RX-7 had was its minimal size and weight, and the compact rotary engine installed behind the front axle helped balance the front and rear weight distribution, which provided a low center of gravity.
In Japan, the Savanna RX-7 was powered with a 12A Rotary engine which has been refined to meet increasingly stringent emissions. The refined 12A Rotary engine produces . In March 1979 Mazda adding a new line-up: the SE which has a sunroof.
In 1980, Mazda introduced a limited run North American model known as the Leathersport, or LS. The LS was essentially an uprated GS with additions such as LS badges on the B-pillars, exterior stripes, gold anodised wheels, brown leather upholstery, leather-wrapped steering wheel and shift knob, removable sunroof, four-speaker AM/FM stereo radio with power antenna (listed as a six-speaker stereo, as the two rear dual voice coil speakers were counted as four speakers), remote power door side mirrors, and standard GS equipment. Two primary options were also available; a 3-speed JATCO 3N71B automatic transmission and air conditioning. The dealer could add other GS options such as a cassette tape deck, splash guards, padded center console armrest, and others. The LS was only available in three exterior colours: Aurora White, Brilliant Black, and Solar Gold. Some sources say 2500 LS model cars were built, while others say production numbers are unknown. The LS had exposed steel bumpers and a high-mounted indentation for the rear license plate, called by Werner Buhler of Road & Track magazine a "Baroque depression."
Series 2 (1981–1983)
thumb|left|Mazda RX-7 Series 2 GSL (US; 1983)
The Series 2, referred to as the FB (produced from 1981 to 1983), had integrated plastic-covered bumpers, wide black rubber body side moldings, wraparound taillights, and updated engine control components. While marginally longer overall, the new model was lighter in federalised trim. The four-speed manual option was dropped for 1981 as well, while the fuel tank grew larger and the dashboard was redesigned, including a shorter gear stick mounted closer to the driver.
In Europe, the FB was mainly noticed for having received a power increase from the of the SA22; the 1981 RX-7 now had on tap. European market cars also received four-wheel disc brakes as standard.
Series 3 (1984–1985)
thumb|left|1984–1985 Mazda RX-7 (Series 3)
thumb|left|Series 3 interior (Canada)
The Series 3 (produced 1984–1985) featured an updated lower front fascia. North American models received a different instrument cluster. The GSL package was continued into this series, but Mazda introduced the GSL-SE sub-model. The GSL-SE had a fuel injected 13B RE-EGI engine rated at and . GSL-SE models 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 4x114.3mm (4x4.5"). They also 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.
The 1984 RX-7 GSL has an estimated 29 MPG (8.11 litres/100 km) highway/19 MPG (12.37 L/100 km) city. According to Mazda, its rotary engine allowed the RX-7 GSL to accelerate from 0 to 80 km/h (50 mph) in 6.3 seconds.
In 1985, Mazda introduced the RX-7 Finale in Australia. This was the last of the series and sold 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 RX-7 has "live axle" 4-link rear suspension with Watt's linkage, a 50:50 front and rear weight distribution, and weighs under . It was the lightest generation of the RX-7 ever produced. 12A-powered models accelerated from 0–97 km/h (60 mph) in 9.2 seconds, and turned 0.779 g (7.64 m/s<sup>2</sup>) laterally on a skid pad. The 12A engine was rated at at 6,000 rpm in North American models, allowing the car to reach speeds of over . Because of the smoothness inherent in the Wankel rotary engine, little vibration or harshness was experienced at high engine speeds, so a buzzer was fitted to the tachometer to warn the driver when the 7,000 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 the North American models. Additionally, North America was the only market to have offered the first generation of the RX-7 with the fuel-injected 13B, model GSL-SE. Sales of the first-generation RX-7 were strong, with a total of 471,018 cars produced; Between 332,850 and 367,878 (seventy to eighty percent) were sold in the United States alone.
RX-7 Turbo
thumb|left|Mazda Savanna RX-7 Turbo
Following the introduction of the first turbocharged rotary engine in the Luce/Cosmo, a similar, also fuel injected and non-intercooled 12A turbocharged engine was made available for the top-end model of the Series 3 RX-7 in Japan. It was introduced in September 1983. The engine was rated at (JIS) at 6,500 rpm. While the peak power figures were only slightly higher than those of the engine used in the Luce/Cosmo, the new "Impact Turbo" was developed specifically to deal with the different exhaust gas characteristics of a rotary engine. Both rotor vanes of the turbine were remodeled and made smaller, and the turbine had a twenty percent higher speed than a turbo intended for a conventional engine. The Savanna RX-7 Turbo was short-lived, as the next generation of the RX-7 was about to be introduced.