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Study Assesses Product Attribute Trade-offs and Technological Progress; Meeting Proposed Obama Fuel Economy Standards Will Require Downsizing and Change in Fleet Mix

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Changes in the attributes (clockwise from upper left, weight, power, fuel economy and torque) of the Honda Accord over time as an example of fleet trends in the US. In contrast, fuel economy actually increased by 15% during that period. Knittel, 2009. Click to enlarge.

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Tsinghua studies on alcohol-gasoline dual fuel engines show fuel efficiency and particle number benefits

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In a second paper, also published in Fuel , they systematically compared the stoichiometric alcohol–gasoline and gasoline–alcohol DFSI combustion for engine particle number (PN) reduction (and fuel economy improvement), also using a high compression ratio gasoline engine. They flexibly controlled the PFI to DI fuel ratios.

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Concept: Honda RD Developing Variable Compression Ratio Engine with Dual Piston Mechanism

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improvement in fuel economy in operation over the Japanese 10-15 cycle. When downsizing, Kato said, using a turbocharger or supercharger to offset the decrease in output can result in a fall in the knocking limit as the boosting pressure rises, causing the thermal efficiency to fall as well. mm with reference to the piston pin.

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Mazdas new SKYACTIV gasoline and diesel engines are steps on the road to its Ideal Engine; focus on compression ratio

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This corresponds to a 23% reduction in fuel consumption and, therefore, CO 2 output.). From a powertrain frame of reference, Mazda is planning a building block strategy—i.e., Extreme compression ratio rather than downsizing. Although downsizing—i.e., knock) and an associated reduction in torque.

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DOE to award up to $137M for SuperTruck II, Vehicle Technology Office programs

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Develop and demonstrate technologies to enable a downsized, boosted, lean, low temperature gasoline combustion engine system that improves fuel economy while meeting emissions requirements. valve faces, piston crowns, and exhaust ports) to improve fuel economy. General Motors. HRL Laboratories, LLC. Description.

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2014 Sprinter van for US standard with new 2.1L diesel; new driver assistance features

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This downsizing enables lower fuel consumption, accompanied by low emissions and optimum weight. The 4-cylinder Sprinter features a 7-speed automatic transmission with torque converter—the only 7-speed automatic transmission to feature in a van—is refined for maximum fuel economy.

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Daimler Trucks NA SuperTruck achieves 115% freight efficiency improvement over 2009 baseline; 50.2% engine BTE

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The Freightliner SuperTruck uses a downsized and downsped 10.7-liter This reduces friction, and increases efficiency and fuel economy. Drivers can run the AC for more than an hour without turning the engine on, resulting in significant reductions in fuel consumption. DTNA SuperTruck technology elements. Click to enlarge.

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