Since the former Toyo Kogyo Motor Corp. introduced the first Japanese rotary car in 1967 (the NSU Spider, launched in 1964, was the world''s first rotary engine production car), the rotary engine has had a roller-coaster ride, one which has been mostly down in recent years since the RX-7 was pulled from the U.S. market.

The first unit, the twin-rotor 10A, had a displacement of 982 cc. The engine, which produced 110 hp and 96 lb.-ft. (130 Nm) of torque, was installed in the Cosmo Sport and Familia.

Next up: the 1,310-cc 13A and 1,146-cc 12A, introduced respectively in 1969 and 1970. Installed in the Luce coupe, the 13A generated 126 hp and 127 lb.-ft. (172 Nm) of torque. The slightly smaller 12A, which produced 120 hp and 116 lb.-ft. (157 Nm) of torque, was developed for the Capella, forerunner of the new Mazda 6 and Atenza.

In 1971 and 1972, the Hiroshima-based auto maker introduced two more rotary cars, the 982-cc Savanna and 1,146-cc Luce. These were powered by variations of the 10A and 12A engines.

Then the unexpected happened. In November 1973, the Arab oil embargo resulted in a quadrupling of petroleum prices. The following year, a controversial report by the U.S. Environmental Protection Agency criticized Mazda''s rotary cars for poor fuel economy. The assessment largely was unfounded, however, because the Cosmo was compared with economy cars of the day, rather than with the sports cars with which the Cosmo had similar performance.

With gas prices rising daily, the company''s fortunes went spinning in reverse. Sales over the next three years dropped 53% (rotary car sales fell 83%), driving Mazda deeply into the red, and the company tottered, if only briefly, on the brink of bankruptcy.

A special project team was set up to save the rotary. Headed by Kenichi Yamamoto, who went on to become president and chairman, the team succeeded in doubling fuel economy over the next three years. Their work culminated in the birth of the RX-7 sports car in 1978 — and the company was back on the road to profitability. In between, Mazda introduced the 1,308-cc 13B on the Parkway bus, Road Pacer sedan, Cosmo AP and Luce Legato. All four models, unable to meet expectations in the marketplace, were phased out by 1981.

With the RX-7''s facelift in 1983, Mazda added a turbocharger to the car''s 1,146-cc engine. The turbocharged 12A produced 130 hp and 119 lb.-ft. (162 Nm) of torque.

Mazda subsequently adopted the engine for the Cosmo and Luce sedans, then introduced a slightly larger 1,308-cc unit, the 13B, on the remodeled RX-7 in 1985. The first-generation 13B produced 185 hp and 181 lb.-ft. (245 Nm) of torque.

Buoyed by the popularity of the RX-7, with sales averaging more than 50,000 units per year since its debut, and blinded by Japan''s economic bubble, Mazda unveiled the world''s first three-rotor rotary, the 20-B, for the luxury Cosmo sedan in 1990. The 1,962cc powerplant, which featured an all-new sequential-twin turbocharger, boosted horsepower to 280 and torque to 297 lb.-ft. (402 Nm).

The introduction of the 3-rotor 20-B was followed by Mazda''s June, 1991, victory at Le Mans with a car powered by an experimental 4-rotor engine, the R26B, and the December launch of a remodeled and significantly upgraded RX-7.

In developing the flagship model, designers pulled out all stops, including liberal usage of aluminum. And they improved the car''s 13B rotary engine, boosting power and torque to the 280-hp/297 lb.-ft. specification of the 3-rotor 20B, while upgrading and reinforcing the car''s suspension and chassis. These improvements resulted in a sticker price nearly double that of the previous model.

And the company was rewarded — initially — by winning several design and engineering awards by enthusiast magazines. When the new RX-7 hit dealer showrooms in Japan and the U.S. in 1993, there was a rush to buy it. First-year sales, despite a significantly higher sticker price, approached 27,000.

Then the sky fell in — both for Mazda and the RX-7. Japan''s economic bubble burst, followed by the sharp rise of the yen in 1994 and 1995. At one point the car''s ¥3.8 million price tag, converted into dollars, reached $47,500.

Exports almost disappeared as total sales crashed to 5,200 in 1995.

Shortly after the arrival of a restructuring team from Ford Motor Co. in 1994, the rotary was put on the back burner. The upscale Cosmo was phased out of production in 1995, and in 1996 the RX-7 was withdrawn from the once-lucrative U.S. market. Since then, sales have averaged about 2,900 units per year, 90% below 1992 levels and 96% under the 1979 peak.

With the launch of the upscale Millenia in 1994, Ford''s management team steered Mazda away from the rotary to the supercharged Miller-cycle engine. Although the car and Miller-cycle V-6 engine got off to an encouraging start, winning several engineering awards, including a string of Ward''s 10 Best Engines awards and one by Popular Science magazine, the Miller-cycle''s progress since then has been disappointing.

And now, with a new and younger management team at Mazda — and with development of the Renesis almost complete — the rotary has come full circle and is primed to make a comeback.

Former Mazda executive and self-appointed rotary historian Tomoo Tadokoro once noted that “every time Mazda gets itself in trouble (often caused by the rotary), it is the rotary which brings the company back to life.”

Mazda rotary sales by year
(in units):
Year Units
1967 343
1968 7,097
1969 28,742
1970 66,169
1971 118,429
1972 154,893
1973 239,871
1974 118,714
1975 86,500
1976 68,277
1977 41,899
1978 80,977
1979 83,218
1980 61,638
1981 60,398
1982 65,902
1983 62,292
1984 68,785
1985 64,673
1986 75,558
1987 52,897
1988 35,662
1989 38,027
1990 34,054
1991 18,323
1992 28,272
1993 7,512
1994 6,397
1995 5,533
1996 4,762
1997 3,556
1998 1,423
1999 4,151
2000 2,611
2001 *2,454
Total 1,800,009
*Jan.-November results