Were actually expecting this Subaru BRZ STI to see at Tokyo Motor Show, but not before the Subaru teases us. At this year November 18, 2011, on the opening day of this year’s Los Angeles Auto Show will reveal, the BRZ Concept.

The Subaru’s new compact sports car concept is based on the new platform developed in collaboration with Toyota. The Subaru BRZ STI concept measures 166.7 inches in length, 70.9 inches in width, and 50.4 inches in height. Subaru’s coupe has a 101.2-inch wheelbase, which should make it very nimble in the corners. For the BRZ STI, Subaru chose a two-plus-two seating layout, which means there’s probably not much room in the back.

In terms of designing, Subaru BRZ STI has several distinctive features. One of them is the low and blade like hood, which was made possible by mounting the engine as low as possible. The BRZ STI was designed with short front and rear overhangs reduce the yaw moment of inertia. At the front, the BRZ STI features a hexagonal grille, hawk eye headlights and fin-shaped fog lamps.

For better aerodynamics, Subaru gave the BRZ STI a lower front spoiler, a huge rear wing for added downforce on the rear axle and a rear diffuser. The bodywork also includes wide rear fender flares, polished stainless-steel quad-tailpipes, and a vented rear bumper. The roof of the Subaru BRZ Concept STI is made from carbon fiber.

The BRZ STI Concept’s exterior is finished in Subaru’s “latest generation” blue, called the WR Blue Pearl II. Subaru BRZ STI has a front engine and rear-wheel-drive architecture and it’s powered by a 2.0liter naturally aspirated four cylinder Horizontally-Opposed Boxer engine. This is a new motor, which was developed entirely by Subaru, was designed to have a square bore and stroke of 86 X 86 mm. Subaru’s new Boxer FA engine will be mated to a six speed manual transmission.

So far, the output of the new Boxer FA engine is a close kept secret, but we do know that this motor will come equipped with a D4-S injection system, that has both direct and port injection. Even though Subaru has not mentioned it yet, we hope that in the future, they’re also going to turbocharge this engine. Just to keep it in line with the tradition started by the Impreza STI, that is.

Subaru says that the production version of the BRZ STI concept will have a low center of gravity. This will improve handling and increase the car’s cornering speeds. Subaru’s official details say that the BRZ STI will offer “Pure Handling Delight”. The BRZ STI is built on a newly developed chassis, featuring a rigid frame housing. For a better front/rear balance, its engine is mounted low and towards the rear of the car. In fact, the engine in the BRZ STI is mounted 4.7 inches lower and 9.4 inches closer to the center of the chassis than in any other Subaru model. The Japanese automaker claims that the BRZ STI has the lowest CoG’s of any car on the market.

An important fact about Subaru’s BRZ concept is the STI part. For the BRZ, Subaru uses an STI-tuned suspension, Brembo brakes and 18-inch wheels. The Subaru BRZ STI is shoed by 215/45R18 tires on the front axle and 225/45R18 tires on the rear one.

Subaru will release the performance details and full specifications of the BRZ STI at the time of its premiere. We hope it will have at least 300 hp, but that will probably put it too close to the Impreza STI.

The production version of the Subaru BRZ STI concept will come in the spring of 2012. This will make it the first mass-produced front Boxer engine sports car with rear-wheel drive in the world.

The Subaru BRZ STI is built on the same platform as the Toyota FT-86 II and the Scion FR-S, but we doubt it will be identical to any of the two models.