Toyota reveals ultra-efficient engines

The new family of engines will give 15 Toyota and Daihatsu models an efficiency gain of up to 30%, including Toyota's new Yaris due in 2015.

The Yaris will be battling for top spot in light car sales with the upcoming Mazda 2 and Ford Fiesta, which will have similar efficiency gains from its skyactiv and EcoBoost technology respectively. The new engines could also help the rumoured upcoming Toyota Rush become the one of the most efficient SUVs in Australia.

The 1.3-litre and 1.0-litre power plants have been co-developed with Toyota's small car brand, Daihatsu. Both units take advantage of an Atkinson cycle, which increases the compression ratio and reduces waste heat to operate more efficiently. However, the Atkinson cycle produces less power than ordinary engines, which has limited its use mainly to Hybrid cars until now.

But Toyota has packed both engines with technology to help retain maximum power while optimising economy. A range of new developments will help the engines breathe better, achieving optimal efficiency. For example, the 1.3-litre will have a cooled exhaust gas recirculation (EGR) system, a redesigned intake port and electronically controlled variable valve timing (VVT-iE).

Both engines are designed to be compatible with stop-start technology, which cuts out the engine in traffic to save fuel. This system is currently limited in small cars to premium offerings, such as the Mini Cooper or the Volvo C30. However, Toyota and Daihatsu could be utilising this feature in the most basic entry level cars.

Both engines will commence production in coming weeks, but we may only get the larger 1.3-litre engine in Australia initially. However the efficiency gains in the 1.0-litre engine could increase the incentive for Toyota to offer a cheap entry level car sourced from Daihatsu, to rival the Suzuki Alto, Nissan Micra and Mitsubishi Mirage.