BMW TwinPower Turbo 4-Cylinder Eco Powerhouse

BMW is aggressively developing plug-in electric vehicles. Indeed, it has established a separate BMW i sub-brand to market EVs and plug-in hybrids like the i3 Megacity and i8 hybrid supercar.. However, BMW is still investing heavily in its core business – great performing ‘Ultimate Driving Machines.’ This means new gasoline and diesel engines that don't compromise performance while reducing fuel consumption and CO2 emissions. Recognizing it will be building internal combustion powered cars for at least a couple of decades, the BMW Group is investing almost $427 million in its engine plants in Munich and Steyr, Austria.

This new engine technology is being developed under BMW's all encompassing EfficientDynamics umbrella. The latest example is a new 2.0-liter, four-cylinder engine that will initially power BMW's new X1 xDrive28i. This compact SUV will be the first four-cylinder BMW sold in the U.S. since 1999.

Like new smaller, high-performance, fuel efficient engines from other manufactures like Ford's EcoBoost, GM's Ecotec, and Chrysler-Fiat's MultiAir, BMW uses a combination of turbocharging, direct injection, and variable valve management to deliver greater output and efficiency from a smaller displacement engine..The BMW four features the automaker’s TwinPower Turbo technology that is already used on the in-line six-cylinder engines powering the 2011 3 Series Coupe and Convertible in 328i and 335i versions. TwinPower technology includes twin-scroll turbocharging direct gasoline injection, double VANOS variable camshaft control and VALVETRONIC variable valve control.

All this adds up to 245 horsepower, 15 more horsepower than the 3.0-liter, inline 6-cylinder used in the 2011 BMW 128i models sold in the U.S. Maximum torque of 258 lb-ft is available at a low engine speed of 1,250 rpm With all-wheel-drive, it gets an average of 30 mpg on the EU test cycle without compromising the performance expected in a BMW. For example, it can accelerate the X1 xDrive28i from 0 to 60 mph in 6.5 seconds.

One of big reasons that more fuel efficient, four-cylinder engines haven't gained wide acceptance in upscale vehicles is that they often were a bit rough running. BMW says the new four is as smooth running as it six-cylinder engines, which are noted for their smoothness. This was achieved by features like vertically offset balance shafts for optimized vibration compensation. In addition, a centrifugal force pendulum integrated into the dual-mass flywheel ensures a noticeable reduction in irregular rotations usually occurring at lower engine speeds. Thus, the engine’s early high torque output is available without any loss in comfort. This vibration damping from the centrifugal force pendulum remains effective across a broad engine speed range.

The new BMW Efficient Dynamics family of engines incorporates a standardized design and a significant number of common components for use in both gasoline and diesel engines. The technology can be used in three-, four- and six-cylinder engines with various power outputs. Next up could be a range of three-cylinder engines for the next-generation MINI and possibly a new entry-level, compact BMW.