The new STi will carry over the familiar 2.0L turbocharged boxer engine in most markets, however, the US will likely get a 2.5L version. An all-new 2.5L engine is currently being developed, which will deliver substantially more juice than the 300hp that’s expected from the 2.0L mill. Instead of increasing the top-end power, engineers have focused on improving the power delivery characteristics of the new range. Expect a much flatter torque curve and more oomph lower in the rev range.
Other mechanical changes include some major revisions so the symmetrical AWD system, including a modified Driver's Control Centre Differential. The new Impreza is also expected to receive a new rear multi-link suspension set-up that should improve both the car’s handling and stability.