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STI engine

2008 Subaru Impreza WRX STI

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2008 Subaru Impreza WRX STI engine

Centerpiece of the STI is the 305 horsepower 2.5 liter turbocharged four-cylinder engine. Silver doohickey on top is the intercooler, which cools intake air after it's been compressed by the turbocharger

Photo © Aaron Gold

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