The second-generation Toyota Aygo will be offered with an all-new 1.0-liter three-cylinder gasoline engine, which promises a higher fuel efficiency thanks to improved thermal and combustion management.
The Japanese automaker states that the engine has a maximum thermal efficiency of 37 percent, which together with other fuel reduction measures, contributes to an alleged improvement of almost 30 percent in fuel consumption compared to current vehicles.
Toyota estimates the Aygo will return a combined fuel consumption of 68.8 mpg UK (4.1 l/100 km or 57.3 mpg US), with CO2 emissions of 95g/km. The 68hp (69PS) engine is also offered on the Japanese market Passo citycar.
Set to arrive this summer in the Aygo, the new engine runs at a higher, 11.5:1 compression ratio than before, with the higher temperatures this creates countered by the adoption of a cooled exhaust gas recirculation system and adjustment of the engine’s valve timing.
The new engine also achieves more efficient combustion with help from a new-shape intake port and piston profile that create a strong tumble flow, with the air-fuel mixture moving in a more even, vertical swirl inside the cylinder.
Toyota says the new engine is also lighter, with features such as an exhaust manifold integrated into the cylinder head. Furthermore, it loses less energy through friction than before.
Alongside the new 1.0-liter engine, Toyota will launch a 1.3-liter petrol unit which uses the Atkinson cycle, a system previously adopted by Toyota for its latest-generation Hybrid Synergy Drive powertrains. Worldwide, Toyota plans to introduce 14 new engine variations based on these units by 2015.
By Dan Mihalascu