Some people consider BMW M cars sleepers because they share their basic platforms with the company's normal models. But, M cars have flares, hood bulges, bigger tires, and aggressively styled bumpers. Anyone with a little car knowledge can spot one from a mile away. But even the most expert enthusiast will have a hard time spotting the performance potential of this car.
Aside from aftermarket taillights and a few stickers on the trunk, this 2014 Civic Si looks totally stock on the outside. Underneath, it's a totally different story. It's got a fully built engine under the hood, with a turbocharger running 16 pounds of boost. According to its owner, this motor sends 450 horsepower and 370 lb-ft of torque to the front wheels, so figure 500 hp or more at the crank.
Matt Farah of got a chance to drive the hotted up Si, and finds it's extremely fun to whip around the canyons. The subtle looks combined with all that power and an limited-slip differential make for one hell of a sleeper.