In addition, lightweight unit-body structures are the foundation for Impreza, Legacy, Outback, and Forester models. These same models have window glass of reduced thickness.
Measures taken under the hood reduce weight, too. All Subaru engines have aluminum-alloy blocks and cylinder heads and all Subaru transmissions have aluminum-alloy cases. Not only does this construction reduce overall weight, it helps to improve the front/rear balance of the vehicle for improved handling. The engines’ pistons have a lightweight design, and the intake manifolds are made of resin, which also contributes to weight reduction.
The 2012 Impreza pushes the envelope farther with optimized lightweight aluminum-alloy wheels and aluminum-alloy rear brake calipers.
Design and Operation
Notice that we’ve only lightly touched upon engines and transmissions. We’ll have more to say about them in the Winter 2012 issue, in which we’ll present additional ways in which Subaru vehicles are built to achieve good fuel economy. In Part Two, we’ll look at vehicle design and how components and systems are engineered to function efficiently.
