Subaru Rex - First Generation

The Rex (K21), introduced 15 July 1972, was the replacement for the Subaru R-2, which was itself the replacement for the long lived, but outdated Subaru 360. Because the R-2 was based largely on the 360, originally including its air-cooled two-stroke engine, it lasted for not even three years. In contrast, the 360 was produced for 11 years and the rear-engined Rex was produced for nine.

The Subaru Rex represented a fresh start designwise, sharing little of its appearance with the Subaru 360, although they were mechanically the same and shared a rear-engine layout. The Rex also retained the 360/R-2's rear swing axle. The appearance of the new Rex was similar to the new larger platform, the Subaru Leone. The Rex originally featured the same water-cooled 356 cc EK34 two-stroke engine as used in the R-2, and was available only as a two-door sedan. In February 1973 a four-door sedan was added, and a three-door "Van" was added in February 1974. The Van was registerable as a commercial vehicle, allowing for considerable savings in taxes and fees. The EK34 engine came with a 32 PS (24 kW) single carburetor on the Custom L, Super L, and other trim levels down to Standard, or a 37 PS (27 kW) double carburetor for the sporty GSR. The TS (Touring Sport) received a 35 PS (26 kW) iteration. The GSR was also somewhat lower than its counterparts, due to radial tires being fitted.

In October 1973 the two-stroke was replaced by a 358 cc rear-mounted, watercooled, two-cylinder, four-stroke engine called the EK21. This produced 31 PS (23 kW) at a peaky 8,000 rpm and 3.0 kg·m (29 N·m; 22 lb·ft) of torque at 6,500 rpm, and featured Subaru Exhaust Emissions Control (SEEC). The car also received a minor facelift (with a "frowny" rather than the smiling grille seen on the turqoise four-door in the infobox being the most obvious difference) and a new chassis code: K22. Front disc brakes were also introduced as an option at the same time. The four-stroke Rex could reach a top speed of 110 km/h (68 mph). The three-door, two-seater "Van" (K42) arrived in February of the next year, when a five-speed version (Custom5) was also added. In September (1974), along with a minor facelift consisting of a new grille and bumpers adjusted to allow for the fitment of larger license plates, a "Wagon" version (K26) appeared. This received four permanent seats, but was no longer registerable as a commercial vehicle and had a considerably lower max load. At the same time, a "Super L" version of the Van was added. Vans and Wagons received a lower tuned engine, with 28 PS (21 kW) at 7,500 rpm; but torque increased somewhat to 3.1 kg·m (30 N·m; 22 lb·ft) at 5,700 rpm. This became the power output of the standard Rex as well for model year 1976 after the SEEC-T (Subaru Exhaust Emission Control - Thermal and Thermodynamic) emissions control system was introduced in December 1975. Torque was down to 2.9 kg·m (28 N·m; 21 lb·ft) at 6,000 rpm. The equipment levels were also reshuffled, with the B-type replacing the Standard and then rising from the AI via the AIG and AII to the AIIG on top. The AII and AIIG versions received disc brakes in front, but the five-speed was no longer available.

In April 1975, the Van received a higher roof and became a four-seater. This was necessitated by Japanese commercial vehicle regulation which require the floor to be completely flat when the rear seat is folded. Because the Rex's engine was mounted in the rear, the cargo floor was rather high, meaning that more head room would be required before a seat could be installed. The Wagon continued in production until the SEEC-T version was introduced in December, but it lost most of its market with the availability of a four-seater Van.