Subaru’s BRZ Concept-STI (Subaru Tecnica International) sports car has been unveiled at the 2011 Los Angeles International Auto Show, ahead of the reveal of the production BRZ at the Tokyo Motor Show. 
The new rear-wheel drive compact sports car features a horizontally-opposed Boxer engine, enabling an ultra-low centre of gravity – producing what Subaru describes as a “pure handling delight.” 
The BRZ Concept–STI displayed in Los Angeles features styling cues developed by Subaru’s STI performance division.
BRZ Concept–STI styling
The hexagonal lower front grille, hawk eye headlights and fin-shaped fog lamps make the front instantly recognizable as a Subaru.
An STI-made lower front spoiler and rear wing magnify down-force and aerodynamic performance, while aiding stable straight driving and excellent handling at high speeds.
The rear design, with bold wheel arch flares, large rear-diffuser and twin dual tailpipes, intensifies the STI performance feel.
A carbon fibre roof is used – a highly acclaimed feature already installed in a WRX STI model in Japan.  This reduces weight and also contributes to the low centre of gravity and amazing handling.
The lively exterior colour is “WR Blue Pearl II” - a new generation of Subaru’s WR blue paint scheme, emphasizing the racing image.
Engine
The BRZ Concept–STI’s Subaru Boxer engine has inherent qualities of light weight, compact size, low centre of gravity, and high rigidity – all pointing toward its great potential in a sports car.  The 2.0-litre horizontally-opposed four-cylinder direct fuel-injection petrol engine has been developed specifically for the BRZ.
The engine has been designed with a square bore and stroke of 86 X 86 mm. Combined with Toyota’s D-4S direct injection technology (fuel injection system), high output and high environmental standards result.
Chassis and body
Compared to other Subaru models, the engine sits an impressive 120 mm lower and is positioned 240 mm closer to the centre of the chassis. As a result, it achieves one of the lowest possible centres of gravity compared to other cars on the market today. 
By including lightweight parts such as the carbon fibre roof, the overall weight has been reduced. The body structure is both lightweight and highly rigid.

Its unique handling performance has been refined by adopting STI’s lightweight 18-inch alloy wheels with performance tires and STI tuned suspension with excellent lateral stiffness.
Brembo brakes enhance braking performance. 
Major specifications
Overall Length × Width × Height (mm): 4230 × 1800 × 1280
Wheelbase (mm): 2570
Engine: 2.0-litre direct fuel injection naturally-aspirated four-cylinder horizontally-opposed Boxer engine
Tyres: 215/45R18 (Front), 225/45R18 (Rear)