Along with their smooth exterior shapes, all 2012 Subaru models have aerodynamic underbody panels. These smooth panels cover the bottom of the engine and some driveline and suspension components to help prevent them from disrupting airflow under the vehicle. Front wheel liners and wheel opening aero flaps also aid airflow efficiency.

On the 2011-2012 Legacy and Outback as well as the 2012 Impreza, the angles of the windshield have been lowered compared to previous generations. The lower angles promote airflow over the vehicles. The front bumpers on the 2012 Impreza also have an optimized aero shape.

Lightweight

Besides shape, weight is one of the prime obstacles to good fuel economy. It takes more power – and, hence, more fuel – to start up a heavy vehicle than a light one and to keep it at speed. Perhaps you’ve noticed the difference in mileage between driving an empty car and one loaded with passengers and cargo. Even the difference of 100 pounds can affect fuel economy.



As a result, manufacturers focus on weight reduction with each succeeding model, despite a corresponding increase in vehicle content (i.e., added and evolved safety systems, audio systems, comfort and convenience equipment).

In order to maintain low curb weights and reduce them wherever possible, Subaru uses technologies in its vehicle bodies and mechanical features that allow lower weight with increased strength. Greater proportions of high tensile strength steel are employed in all Subaru bodies, and strong, lightweight metals are used in components throughout the model lineup.
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