The History Of Mazda Efini RX-7


The Mazda RX-7 is a sports car produced by the Japanese automaker Mazda from 1978 to 2002. The original RX-7 featured a 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 coupé. The compact and light-weight Wankel engine or rotary engine is situated slightly behind the front axle, a configuration marketed by Mazda as "front mid-engine". It was offered in America as a two-seat coupé, with optional "occasional" rear-seats in Japan, Australia, and other parts of the world.

The RX-7 made Car and Driver magazine's Ten Best list five times. In total, 811,634 RX-7s were produced.

  • 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).

  • 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."[citation needed]
  • 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 135lb·ft (183N·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 air-oil oil cooler was reintroduced, after being dropped in the 1983 model-year for the controversial "beehive" water-oil heat exchanger.

The 1984 RX-7 G has an estimated 29 highway miles per gallon (8.11 litres per 100km) / 19 estimated city miles per gallon (12.37 l/ 100km). According to Mazda, its rotary engine, licensed by NSU-Wankel allowed the RX-7 G to accelerate from 0 to 50 (80 km/ h) in 6.3 seconds. Kelley Blue Book, in its January-February 1984 issue, noted that a 1981 RX-7 G retained 93.4% of its original sticker price.

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 2600 lb (1180 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 100hp (75kW) at 6000 rpm, allowing the car to reach speeds of over 120 mph (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[citation needed].

The 12A engine has a long thin shaped combustion chamber, there is a large surface area in relation to its volume. So 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. 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.

  • Series 4 (1986–1988) was available with a naturally aspirated, fuel-injected 13B-VDEI producing 146hp (108kW). An optional turbocharged model, known as the Turbo II in the American market, had 189 hp (135kW).
  • 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 Series5 FC made 160hp (119kW), while the Series5 Turbo made 200hp (147kW).

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 928. Mazda's stylists, lead by Chief Project Engineer Akio Uchiyama, actually focused more 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. 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. 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.

Though about 80lb (36kg) 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 1991, an outright horsepower "arms race" broke out between sports car manufacturers, with higher and higher levels of power required to meet buyer demands.

Mazda sold 86,000 RX7'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.

Convertible

Mazda introduced a convertible version of the RX7 in 1988 with a normally aspirated engine — introduced to the US market with ads featuring Hollywood actor James Garner, at the time featured in many of Mazda's television advertising.

The convertible featured a removable rigid section over the passengers and a folding textile rear section with heatable rear glass window. Power operated, lowering the top required unlatching two header catches, power lower the top halfway, exiting the car, folding down the rigid section manually, and then further power-lowering the top. Mazda introduced with the convertible the first integral windblocker, a rigid panel that folded up from behind the passenger seats to block unwanted drafts from reaching the passengers — thereby extending the driving season for the car in open mode. The convertible also featured optional headrest mounted audio speakers and a folding vinyl snap-fastened tonneau cover. The convertible assembly was precisely engineered and manufactured, and dropped into the ready body assembly as a complete unit — a first in convertible production.

Several leading car magazines at the time also selected the convertible as the best rag-top available on the market[citation needed]. Mazda exported approximately five thousand convertibles to the United States in 1988 and fewer in each of the next three model years, although it is difficult to confirm these figures, as Mazda USA did not keep RX-7 import records by model type. Production ceasing in October 1991 after Mazda marketed a limited run of 500 example for 1992 for the domestic market only. In Japan, the United Kingdom, and other regions outside the US, a turbocharged version of the convertible was available.

The third and final generation of the RX-7, FD (with FD3S for the JDM and JM1FD for the USA VIN), was an outright, no-compromise sports car by Japanese standards. It featured an aerodynamic, futuristic-looking body design (a testament to its near 11-year lifespan). The 13B-REW was the first-ever mass-produced sequential twin-turbocharger system to export from Japan, boosting power to 255PS (188kW; 252hp) in 1993 and finally 280PS (206kW; 276hp) 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. Only the 1993–1995 model years were sold in the U.S. and Canada. Series 6 came with 255PS (188kW; 252hp) and 294N·m (217ft·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.
  • 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 10PS (7kW). 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 1280kg (2822lb). Power was 280PS (206kW; 276hp), with 313.8N·m (231ft·lbf) of torque as per the maximum Japanese limit. The 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. They still command amazing prices on the Japanese used car scene years later.

- There are three kinds of "Spirit R": the "Type A", "Type B", and "Type C". The "Type A" has a 5-speed manual transmission, and is said to have the best performance of the three models. The "Type B" has a 2+2 seat configuration and also sports a 5-speed manual transmission. The "Type C" is also a 2+2, but has a 4-speed automatic transmission. Clarification of the build number breakdown for each type is sought as Mazda hasn't publicly published the production figures.

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

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 10psi (69kPa) of boost from 1800rpm, and the 2nd turbocharger was activated at 4000rpm and also provided 10psi. The changeover process, between 3500rpm and 4000rpm, provided 8psi (55kPa), was incredibly smooth, and provided linear acceleration and a very 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 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.

Australia had a special high performance version of the RX-7 in 1995, dubbed the RX-7 SP. This model was developed as a homologated road-going version of the factory race cars used in the 12hr endurance races held at Bathurst, New South Wales, beginning in 1991 for the 1995 event held at Eastern Creek, Sydney, New South Wales. An initial run of 25 were made, and later an extra 10 were built by Mazda due to demand. The RX-7 SP produced 204kW (274hp) and 357N·m (263ft·lbf) of torque, compared to the 176kW (236hp) and 294N·m (217ft·lbf) of the standard version. Other changes included a race developed carbon fibre nose cone and rear spoiler, a carbon fibre 120L fuel tank (as opposed to the 76L tank in the standard car), a 4.3:1-ratio rear differential, 17in diameter wheels, larger brake rotors and calipers. An improved intercooler, exhaust, and modified ECU were also included. Weight was reduced significantly with the aid of further carbon fibre usage including lightweight vented bonnet and Recaro seats to reduce weight to just 1218kg (from 1310kg). It was a serious road going race car that matched their rival Porsche 911 RS CS for the final year Mazda officially entered. The formula paid off when the RX-7 SP won the title, giving Mazda the winning 12hr trophy for a fourth straight year. A later special version, the Bathurst R, was released in 2001 to commemorate this, in Japan only.

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 till 1995. 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 such as 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.

Grand Total:..13,879

Racing versions of the first-generation RX-7 were entered at the prestigious 24 hours of Le Mans endurance race. The first outing for the car, equipped with a 13B engine, failed by less than one second to qualify in 1979. The next year, a 12A-engine car not only qualified, it placed 21st overall. That same car did not finish in 1981, along with two more 13B cars. Those two cars were back for 1982, with one 14th place finish and another DNF. The RX-7 Le Mans effort was replaced by the 717C prototype for 1983. In 1991, Mazda became the first Japanese manufacturer to win the 24 hours of Le Mans. The car was a 4-rotor prototype class car, the 787B. The FIA outlawed rotary engines shortly after this win. To this day the rotary powered Mazda is the only Japanese manufacturer to have ever won the prestigious 24 hour Le Mans race outright.[citation needed]

Mazda began racing RX-7s in the IMSA GTU series in 1979. That first year, RX-7s placed first and second at the 24 Hours of Daytona, and claimed the GTU series championship. The car continued winning, claiming the GTU championship seven years in a row. The RX-7 took the GTO championship ten years in a row from 1982. The RX-7 has won more IMSA races than any other car model.

The RX-7 also fared well at the Spa 24 Hours race. Three Savanna/ RX-7s were entered in 1981 by Tom Walkinshaw Racing. After hours of battling with several BMW 530i and Ford Capri, the RX-7 driven by Pierre Dieudonné and Tom Walkinshaw won the event. Mazda had turned the tables on BMW, who had beaten Mazda's Familia Rotary to the podium eleven years earlier at the same event. TWR's prepared RX-7s also won the British Touring Car Championship in 1980 and 1981, driven by Win Percy.

Canadian/ Australian touring car driver Allan Moffat was instrumental in bringing Mazda into the Australian touring car scene. Over a four year span beginning in 1981, Moffat took the Mazda RX-7 to victory in the 1983 Australian Touring Car Championship, as well as a trio of Bathurst 1000 podiums, in 1981 (3rd with Derek Bell), 1983 (second with Yoshimi Katayama) and 1984 (third with former motorcycle champion Gregg Hansford). Australia's adoption of international Group A regulations, combined with Mazda's reluctance to homologate a Group A RX-7, ended Mazda's active participation in the touring car series at the end of the 1984 season.

The RX-7 even made an appearance in the World Rally Championship. The car finished 11th on its debut at the RAC Rally in Wales in 1981. Group B received much of the focus for the first part of the 1980s, but Mazda did manage to place third at the 1985 Acropolis Rally, and the Familia 4WD claimed the victory at Swedish Rally in both 1987 and 1989.

The RX-7 is considered as a popular choice in import drag racing, during the late nineties toward 2004 Abel Ibarra raced a spaceframe FD which averaged no less than high 6 seconds passes, until he replaced it with a spaceframe RX-8, the FD was later to shipped and sold to an Australian.

The FC and FD is considered a popular choice for drifting contests, given the long wheelbase and an average of 450bhp (336kW). Youichi Imamura won the D1 Grand Prix title in 2003 and Masao Suenaga narrowly lost his in 2005, both in FDs.

The RX-7 is a popular choice among autocross drivers.[citation needed]

In Japan, the RX-7 has always been a popular choice in domestic events, competing in Group 5 based Formula Silhouette to its modern day incarnation, the Super GT series from when the Japan Sport Sedan series would become the GT300 category which it had been competing in. Its patience would pay off as in 2006, RE Amemiya Racing Asparadrink FD3S won the GT300 class championship.

In New Zealand a large and growing motorsport class called Mazda Pro7 Racing makes use of the series 1, 4 and 6 RX-7s for one make circuit racing. They run an average of 8 x 2 day meetings a season and racing can see up to 30 RX-7s on the track at any one time.




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