Introduced for the 2012 Super GT season the Subaru BRZ GT300 is powered by a four cylinder boxer engine called the EJ20. It is based on the experience and know-how the Japanese marque accumulated over its years in the World Rally Championship, but also incorporates some cutting edge technology.

STI worked closely with R&D Sport, the team that developed the BRZ as well as its Legacy based forerunner. The location of engine mounts and overall engine bay shape was defined by the R&D sport engineers.

The layout of the intake and cooling system was also a major consideration for both the STI engineers and those on the chassis side. A key stipulation from Subaru was that there should be minimal changes to the cars look and silhouette which limited cooler placement and intake design.
The main heat exchanger and intercooler are totally split in a bi-plane arrangement. The heated air exits via ducting on the bonnet of the car, and is channelled away from the cockpit. This is especially important at races run in very high temperatures such as the 300km race at Sepang.

Efficient radiator design was key to this task and and the main heat exchanger also contains an oil cooler.

Looking at the engine from below you can see how the exhausts exit below the cylinder heads, this means the engine sits higher than it could do and negates some of the low centre of gravity benefits of the boxer design. The whole exhaust manifold is wrapped in a metallic thermal barrier, inste...