Subaru is readying a longer, roomier and sportier looking WRX sedan to separate the high-performance car from its sibling -- the compact Impreza. The 2015 WRX features a new 268-hp, 2.0-liter direct-injection turbo boxer engine and a six-speed manual transmission. A continuously variable automatic transmission will be optional. It sits on a modified Impreza platform but features an all-new body. It goes on sale March 15 in the United States and will be offered only as a sedan; the five-door hatchback has been dropped.