2010 Subaru Impreza WRX STI Special Edition - Click above for high-res image gallery
Rumblings about a diesel-powered Subaru WRX STI first surfaced more than two years ago, and now they're back. The realities of meeting CO2 emissions limits in Europe and elsewhere may have increased the likelihood of a high-performance diesel Subaru, and an oil-burning STI would probably generate at least 200 horsepower and well over 300 pound-feet of torque, suggests Autocar. According to the UK rumor-traffickers, gasoline engines will almost certainly remain in the mix, albeit with reduced displacement. A new engine based on the 1.5-liter boxer in the base Impreza could offer suitable power if mixed with other technologies like direct injection. Even if Subaru does indeed develop a diesel STI, there's no guarantee that such a model would ever make it to North America.
Of course, the WRX doesn't live in a vacuum. Its longtime rival, the Mitsubishi Lancer Evo may also ditch the spark plugs and also add a hybrid system. Earlier plans for a gas hybrid were reportedly canceled in favor of the diesel. The plan is to retain the Evo's sophisticated all-wheel-drive for acceleration to 60 mph in under five seconds and CO2 emissions below 200 grams per kilometer. Thanks to everyone for the tips!