The Mazda RX-5 was an automobile model which was produced from 1975 through 1980. It was a small luxury sporty coupe intended to compete with the Ford Thunderbird and similar vehicles. It was called Rx-5 in Australia, and 'Mazda Cosmo in the Japanese and American market .
It shared much of its mechanicals with the Mazda RX-4, with the addition of rear 5 link coil suspension and rear disc brakes. JDM models were available with the 12A engine but all overseas models used the 13B engine, which had by that time been debugged from the problem of failed combustion chamber seals, but still had a high frequency of gasket failures between the aluminum and iron sections of the engine housing, due to differential thermal expansion of the dissimilar metals.
It was extremely popular in Japan, due to its American style and high performance and luxury, but sold only in limited numbers in rest of the world. The RX-5 was retired in the American Mazda lineup to make room for the new 1979 Mazda RX-7.
A related RX-6 model was offered in some markets with the same bodyshell and premise.
Mazda RX-5 1975 - 1981
The second generation CD Cosmo appeared in 1975 and lasted until 1981. It was known as the Cosmo AP in Japan, and sold internationally as the Mazda RX-5, though in some export markets its piston powered counterpart was called the Mazda 121 (a name later applied to Mazda's subcompact model). Mazda America used the Mazda Cosmo name and offered it from 1976 through 1978. The CD Cosmo/RX-5 series was a flop internationally as Mazda tried too hard to "Americanize" the car. It was however an enormous success in Japan where over 55,000 where sold in the first year alone. Due to its poor sales as an export, the series-II version from 79-81 was not exported and remained on domestic sale only.
The Cosmo was Mazda's 'large' compact rotary coupe and based on the Mazda RX-4 floorpan and mechanics, but slightly heavier due to body design and more luxurious appointments, including an 5-link rear suspension and rear disc brakes. It was available with the 12A and 13B engines.
The Cosmo was affectionately referred to as the Japanese Grand Prix, and indeed was fitted out to compete with that class of American road cruisers. With the standard manual transmission, it was a surprisingly quick and responsive car to drive - as proven to the chagrin of many comparable sporty coupe drivers. Comfortable and well-equipped, it suffered from the bane of many Japanese automobiles (and American as well) of the period - poor rust-proofing and premature rusting. The rotary engine responded in an almost rheostat mode once it was above 2500 rpm, smoothly and quickly winding to the red line.
A piston engine version, the Cosmo 1800, used a 1769 cc (80x88 mm) straight-4 SOHC engine that produced 100 hp (75 kW) and 110 ft·lbf (149 N·m).
Wheelbase: 2510 mm
Front Track: 1380 mm
Rear Track: 1370 mm
Length: 4470 mm
Width: 1680 mm
Weight: 1120 kg
Mazda RX-5 1982 - 1989
The third generation HB Cosmo from 1982 shared the Mazda HB chassis with its twin, the Mazda Luce. The Cosmo name was available on a coupe, hardtop and sedan body. Its equal Mazda Luce variant was not available in coupe form. The HB Cosmo/Luce was the only car in automotive history to option all three forms of Automotive engine. Piston, Diesel and Rotary.
Mazda offered three versions of rotary engine for the HB series. A 12A-SPI, 12A-turbo and 13B-RESI. The latter available with automatic transmission only. The 1982 12A-turbo Cosmo coupe was officially the fastest production car in Japan at one stage.
The HB Cosmo was sold with its rotary engine option in Japan only. The sedan variant was replaced in 1986, but the Cosmo soldiered on unchanged until 1989.