BMW revealed details and pictures of new 3-Series Coupe and Convertible, which feature a subtle facelift, tweaked powertrain for the 328i, as well as a new turbocharged six-cylinder engine for the 335i models.  Known as the N55, this turbo engine is a 3.0 liter six-cylinder inline. BMW is still reluctant to try V6, but it’s ok because the N55 is an engineering marvel capable of 300 hp and 300 lb-ft of torque.

This engine is based on the N54 inline-6 which is used in the current 3er Coupe and Convertible, but it comes with a new type of turbochargers which are more efficient and it also has BMW’s Valvetronic system, which in essence is clever way to control valves for more power and less fuel consumption.

It’ll come mated to either a six-speed manual or a Steptronic six-speed auto, and since the torque power is available form a lower rpm than the previous models, at least on paper, it should be faster. A Coupe 3er equipped with this engine and manual gearbox will do zero to 60mph in 5.3 seconds. But the main advantage is the fuel economy, as they say the N55 is about 10 percent more efficient.

The other variant will be the 328i, powered by the same 3.0-liter inline-6 engine (N52)  but without turbochargers. It has 230 horsepower, 200 lb-ft. This engine hosts a number of enhancements for the sake of being lighter and more efficient, including aluminum/magnesium engine block, hollow camshafts, plastic camshaft cover, improved combustion chambers, a further evolved Double VANOS, higher fuel injection pressure, sophisticated engine electronics, an electric coolant pump, a variable-volume oil pump and an oil/coolant heat exchanger. BMW also offers a four-wheel-drive variant, but only with the Coupe version.

As for design, the car is basically the same as the 2010 models, but it’s got a nose job. It features a new and sleeker front bumper and slightly revised tail and headlamps with LEDs at the back. Furthermore, the 2011 3er comes with slightly extended front and rear overhangs, and newly designed side mirrors. Three new colors including Deep Sea Blue Metallic, Vermillion Red Metallic, and Mineral White Metallic exterior are now available for both Coupe and Convertible as well.

The interior remains more or less unchanged in term of design but it comes with upgraded trims, offering different combinations of leather and wood decoration.