Toyota has unveiled its new Atkinson-cycle engines
Toyota has recently unveiled two all-new small-displacement petrol engines, specifically designed to make the next-gen Toyota compact cars at least ten percent more fuel efficient than the current models.
According to plans from the Japanese manufacture, fourteen variations of the all-new 1.0-litre three-cylinder and 1.3-litre four-cylinder petrol engines will be introduced in total, the first one launching in 2015.
Toyota is approaching the industry-wide trend of improving engine efficiency a bit differently than their American counterparts. While most other companies are going towards downsizing, direct injection and turbocharging technologies, the Japanese have employed the Atkinson burning cycle which they have combined with high compression ratios and a rapid combustion process.
The Japanese company has only used the Atkinson cycle in its hybrid vehicles but these new engines won’t be teamed with electric motors. The burning process in the Atkinson cycle improves fuel efficiency by maintaining the intake valve open for a quick moment during the compression stroke, though its downside is reduced power and torque.
According to Toyota, they have partially combated this by running its high compression ratios, 11.5 for the three-cylinder engine and 13.5 for the four-cylinder, just a bit under the 14.0 achieved by rival Mazda.
The Japanese company has also prepared other innovations to help the fuel efficiency including a newly shaped intake port as well as a cooled exhaust gas recirculation system.
The 1.3-litre engine also features their trademark Variable Valve Timing-intelligent Electric technology with the aim of improving combustion and reducing loss. The duo will also be available with start-stop technology.
When all the fuel consumption reduction technologies are combined, Toyota claims that they will make the vehicles powered by their larger engine approximately 15 percent more efficient than the current models while those equipped with the smaller unit can get to up to 30 percent more efficient.
The company has not announced which vehicles will be getting the engines, but they are expected to launch at start in compact models for the Japanese market.
