Mazda Cosmo

Mazda Cosmo at a glance

Development and production history

The Cosmo Sport was Mazda's showcase for the Wankel rotary engine. English Wikipedia credits Heiji Kobayashi and Kenichi Yamamoto in the car's infobox. A prototype appeared at the 1964 Tokyo Motor Show, about a month before the Tokyo Summer Olympics. Mazda then built 80 pre-production cars in 1965–1966: 20 for its own test department and 60 for dealers to test in everyday use.

Full production began in May 1967. The Series I, code L10A, was built until July 1968 (343 cars). The Series II, code L10B, followed from July 1968 to September 1972 (833 cars) with more power, a five-speed gearbox, 15-inch wheels, power-assisted brakes and a wheelbase lengthened by 15 cm to 2,350 mm. All 1,176 cars were assembled by hand at a rate of about one a day.

The price was 1.48 million yen for the L10A in 1967, about US$4,100, lower than the Toyota 2000GT. The L10B of 1968 was again 1.48 million yen, quoted at US$4,390. The rival from Toyota is described in our Toyota 2000GT article.

Design and engineering

The Cosmo Sport is a two-seat coupé. Brakes were 10-inch discs at the front and 7.9-inch drums at the rear; the L10B added power assistance. The L10A rode on 14-inch wheels and the L10B on 15-inch wheels.

The Series II has a wheelbase of 2,350 mm, 15 cm longer than the Series I. The car is also remembered for its role in Japanese television: English Wikipedia mentions it in The Return of Ultraman.

The 10A rotary engine

The 10A has two rotors and a displacement of 982 cc. In the L10A (engine type 0810) it was fed by a Hitachi four-barrel carburettor and produced about 82 kW (110 hp). The L10B engine (type 0813) produced 95 kW (128 hp) and 140 N·m (103 lb·ft) of torque.

On paper the L10B produces about 97 kW per litre of displacement. Our power converter gives the hp figures in kW and PS.

Mazda Cosmo Sport specifications

The 1968 Marathon de la Route

The Cosmo's only racing outing was the 84-hour Marathon de la Route at the Nürburgring in 1968. Mazda entered two almost standard cars among 58 others, with engines limited to 96 kW (130 PS). The all-Japanese crew retired in the 82nd hour with axle damage. But the car driven by a Belgian crew finished fourth overall, a strong result for a new engine type in an endurance race of three and a half days.

The Cosmo Sport in numbers

The production figures in English Wikipedia give a clear picture of how exclusive the first Cosmo was. The 343 Series I cars make up 29% of the total and the 833 Series II cars 71%. Spread over the 64 months from May 1967 to September 1972, the 1,176 cars correspond to fewer than 20 a month, consistent with the hand assembly of about one car per working day. The Eunos Cosmo of the 1990s sold about seven and a half times as many cars as the original.

The step from L10A to L10B was significant. Power rose from about 82 kW to 95 kW, or by about 16%, the quarter-mile time fell from 16.4 to 15.8 seconds, and the top speed went from 185 km/h to over 193 km/h. At the same time the price stayed at 1.48 million yen. In US dollars English Wikipedia quotes US$4,100 for the L10A (1967) and US$4,390 for the L10B (1968); the source notes that the price rose slightly. Our power-to-weight calculator compares such figures with other cars.

Later Cosmo generations

After the Cosmo Sport the name moved up-market. The CD generation of 1975 was offered as the fastback Cosmo AP (RX-5) and the notchback Cosmo L, with rotary or piston engines. The HB of 1981 shared its chassis with the Luce and added a diesel. And the JC of 1990 returned to a 2+2 coupé with twin sequential turbochargers. The last Cosmo, sold under Mazda's Eunos brand, offered the three-rotor 20B engine, rated at about 206 kW (280 PS), as well as the twin-rotor 13B-RE. With 8,875 cars it was also far more common than the original Cosmo Sport. More of Mazda's history is in our history of Mazda.

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