Driving engine efficiency

A collaboration between the Schaeffler Group and Fiat Powertrain has resulted in the development of what is claimed to be the world’s first fully variable hydraulic valve-control system for car engines.

The Uniair system was originally developed by engineers at the Centro Ricerche Fiat (CRF). In 2001 Fiat granted a licence to Schaeffler to continue to develop the technology and in 2003 the first functioning Schaeffler prototype car was available, with further prototype vehicles manufactured two years later. In 2004 the development of the Fiat Fire Multiair engine was started.

The final specification of the system was completed in 2007 and manufacturing facilities for series production started at various Schaeffler Group locations in the same year. Since 2009, the company has been working with Fiat and Alfa Romeo to develop specific bespoke versions of the technology for their new lines of cars.

In conventional cam-actuated valve systems, a mixture of fuel and air is forced into the cylinder of an engine through an intake valve. The valve then closes and the fuel-air mixture is compressed and ignited – after which the products of combustion exit through an exhaust valve.