mk1

In April 1978, Toyota began production of the Supra in Japan, as the Celica XX, and sold it alongside the Celica at Japanese dealership sales channels called Toyota Corolla Store.

The Supra was offered with a 125 PS (92 kW; 123 hp) 2.0 L 12-valve SOHC inline-six engine (M-EU, chassis code MA45) or the 82 kW (110 hp; 111 PS) 2.6-liter 12-valve SOHC inline-six engine (4M-E, chassis code MA46). The Japanese model was equipped with the smaller 2.0 L engine so that buyers would not incur an additional tax under vehicle size and engine displacement regulations. Both engines were equipped with electronic fuel injection.^[6][9] The installation of the larger engine did obligate Japanese buyers to pay a higher annual road tax, making owning the car more expensive than the smaller Celica.

The Supra was first exported outside Japan in January 1979.^[10] The federalized model was originally equipped with a 110 hp (82 kW; 112 PS) 2.6-liter 12-valve SOHC inline-6 engine.

Transmission options for the model were either a 5-speed manual (W50) or an optional 4-speed automatic transmission (A40D). Both transmissions featured an overdrive gear. The top gear in the 5-speed was its overdrive gear whereas the automatic transmission featured an overdrive gear that would engage at speeds over 56 km/h (35 mph). The drivetrain for the Supra retained the T series solid rear axle configuration of the Celica in the Japanese MA45 version and a larger F series (and optional Limited Slip Differential) in the MA46 and MA47. The car also came standard with 4-wheel disc brakes and featured a four-link rear suspension with coil springs, lateral track bar, and stabilizer bar. The front suspension consisted of MacPherson struts and a stabilizer bar.

The interior of the Supra had optional power windows and power locks as part of the convenience package. The convenience package also included cruise control and special door trim with door pull straps with an optional sunroof. As for standard features, in the centre console there was an extendable map light and a flip-top armrest, which provided storage. Some other features were the tilt steering wheel, deep zippered pockets on the backs of the front seats, and a tonneau cover under the liftback. The dashboard also contained a state of the art AM/FM/MPX 4-speaker stereo radio, analog clock, and tachometer as part of the instrument panel