Leading the attack on engine pumping losses

Cylinder deactivation delivers real-world fuel economy gains, helping vehicles to meet and exceed their sticker numbers. That's why the downsized/boosted guys now want it on their engines.

Powertrain engineers talk about the advantage of having more “knobs to turn”-technologies that work synergistically to reduce fuel consumption and help increase vehicle efficiency. For the past decade, direct injection and turbocharging have been a popular “knob” for enabling downsized gasoline engines to perform like larger-displacement ones while consuming less fuel. Meanwhile, cylinder deactivation has helped big engines deliver surprisingly good economy, while keeping deep reserves of torque available when the driver's right foot demands it.

Until recently, the technologies have mostly remained separate in the powertrain planners' toolbox. Their adoption has sometimes raised debate as to which is the most effective in terms of real-world fuel economy, unit cost, and performance. But the stringent CO₂ emission demands of Euro6, U.S. 2025 CAFE, and new Asian regulations have engineers searching for solutions that leverage both.