MultiAir technology

MultiAir is an award winning (International Best New Engine of the Year 2010, 1.4 TB MultiAir) innovative technology fitted to the most recent Alfa Romeos. MultiAir represents an important break with the current petrol engine scenario, just as Common Rail engine was at the launch of the Alfa Romeo 156 in 1997.

From a technical viewpoint, the MultiAir takes the spark-ignition engine to limits of efficiency that were once unthinkable. MultiAir technology allows the lift profile of the valves to be modified in response to the request for air from the engine. The results of this system are truly revolutionary: it is also possible to open the same valves twice during the same cycle, surpassing the structural limits of the mechanical camshafts.

This is a significant achievement from an environmental and economic perspective: the MultiAir reduces fuel consumption and CO₂ emissions

Benefits

The main advantages of MultiAir:

• Maximum Power is increased by between 10% and 35% thanks to the adoption of a power-orientated cam profile
• Low rpm torque is improved by up to 15% thanks to direct control over valve opening
• An improvement of up to 12% in acceleration thanks to the greater air mass pressure
• A reduction of up to 10% in fuel consumption and carbon dioxide emissions, thanks to the elimination of pumping losses.

Technical explanation

MultiAir technology allows much more flexible control of the engine's air intake compared to mechanical distribution systems.

The system is based on the insertion of an amount of oil between the cam and the intake valve, which can be varied through an 'on-off' type solenoid valve, in turn controlled by an electronic control unit. With this system, the valves open and provide air according to the varying demands of the engine.

Different valve opening and closing strategies are employed to optimise the efficiency of combustion. The constant air pressure up stream valves and the improved dynamics of the system eliminate any delay in torque response, thus greatly enhancing the pleasure of the driving experience.