2013 Subaru Impreza Road Test and Review: Engines and Fuel Economy
- No changes for 2013
A long-standing Subaru characteristic is a 4-cylinder or 6-cylinder “boxer” engine, so named for its horizontally opposed cylinder structure in which the pistons jab outward from the crankshaft like the fists of a prizefighter. Boxer engines are also called “flat-fours” and “flat-sixes” because, unlike an inline- or V-type engine, they lay flatter within the engine bay. A byproduct of such design is a lower center of gravity, which contributes to greater stability and improved handling.
The boxer engine in the 2013 Impreza is a 2.0-liter 4-cylinder developing 148 horsepower and 145 lb.-ft. of torque, paired with a 5-speed manual gearbox or a Lineartronic continuously variable transmission (CVT). This engine makes the Impreza a Partial Zero Emission Vehicle (PZEV), and is rated by the EPA to get 28 mpg in combined driving with the manual transmission and 30 mpg with the CVT. I averaged 26.4 mpg and spent most of my time driving on the highway. That’s not in the same neighborhood as 30 mpg, but is still pretty good for what Subaru calls “the most fuel-efficient all-wheel-drive car in America.”
All-wheel drive, a rarity in small cars, is standard equipment. Imprezas equipped with a manual transmission have a continuous AWD system that splits engine power 50:50 between the front and rear wheels via a viscous-coupling locking center differential. If the front or rear wheels slip, the system automatically routes more power to ones with grip. Versions with a CVT, like my test car, have an Active Torque Split AWD system that delivers power to the Impreza’s front wheels until they slip, at which point the system automatically distributes power to the rear wheels.