Toyota announced today that it is working on a new generation of highly fuel-efficient engines that will be introduced globally by 2015. A total of 14 new engine variations will be used in models scheduled for partial redesign in the near future, with their most important quality being the “outstanding thermal efficiency.
One of the engines is a 1.3-liter gasoline engine in which Toyota is employing the Atkinson cycle
, normally used in dedicated hybrid engines. Use of the Atkinson cycle provides an increased expansion ratio and reduces waste heat through a high compression ratio (13.5), resulting in superior thermal efficiency
Toyota Previews All-New 1.0-Liter and 1.3-Liter Engines, Up to 30 Percent More Economical - Carscoops
Toyota aims to further improve the fuel efficiency of the engine by utilizing other innovations including an intake port with a new shape that generates a strong tumble flow (whereby the air-fuel mixture flows in a vertical swirl) inside the cylinder, and a cooled exhaust gas recirculation (EGR) system paired with Variable Valve Timing-intelligent Electric (VVT-iE) technology to improve combustion and reduce loss. [/FONT][FONT=Verdana]Toyota says the new engine will have a maximum thermal efficiency of 38 percent, top-level among mass-produced engines. The engine will thus be approximately 15 percent more economical compared with current vehicles