The Subaru F-9X was a concept car shown at the Tokyo Motor Show in 1985, developed by Fuji Heavy Industries as a sports-oriented coupe study rather than a production model.
Its rounded, aerodynamic bodywork stood in sharp contrast to the angular wedge shape of the contemporary XT coupe. The front, rear and door glass curved up into the roofline, giving the cabin the appearance of a glass dome. The soft-edged nose featured arched headlight covers and a pronounced front apron, with an unusual deep body-side opening between the headlights and front wheel arches for airflow, along with air slits at the front of the bonnet. Beneath the doors, the flanks were shaped into channels directing air to the rear brakes, while the rear fenders extended into tailfins linked by a large rear wing. The body shape was developed by FHI's aircraft division and used composite materials, including Kevlar and carbon fibre in a sandwich construction, to keep weight low while maintaining aerodynamic efficiency.
The car used a flat-four boxer engine derived from Subaru's mid-range 1.8-litre unit, enlarged to two litres and fitted with DOHC cylinder heads and 16 valves. It combined both a turbocharger and a supercharger with intercooling, producing 360 hp at 8000 rpm and 343 Nm of torque at 6000 rpm. Sources differ on the drivetrain layout: some accounts describe a permanent four-wheel-drive system with a lockable center differential and a rear differential brake, while others list it as rear-wheel drive. The chassis was equipped with wide Michelin MXX tyres, and estimated top speed was 300 km/h.
