The gasoline engine is a , 1.0 litre, ECA series 3-cylinder unit providing lean burn operation with an air-to-fuel ratio that can reach 25.8 to 1. The engine uses lightweight aluminum, magnesium, and plastic to minimize weight. The electrical motor assist adds another (at 3000 rpm) and a maximum of 36 pound-feet (49 Nm) of torque when called on, resulting in at 5700 rpm and of torque at 2000 rpm, with the aim to boost performance to the level of a typical 1.5 L petrol engine. It also acts as a generator during deceleration and braking to recharge the vehicle's batteries, and as the Insight's starter motor. (This improves fuel efficiency and extends the lifetime and fade resistance of the brakes, without adding unsprung weight). When the car is not moving, for example at a stop light, the engine shuts off. Power steering is electric, reducing accessory drag.