MultiAir

Fiat 875 cc two cylinder TwinAir engine featuring Multiair technology

MultiAir or Multiair is a hydraulically-actuated variable valve timing (VVT) and variable valve lift (VVL) engine technology enabling "cylinder by cylinder, stroke by stroke"[1] control of intake air directly via a gasoline engine's inlet valves. Developed by Fiat Powertrain Technologies, the technology addresses a primary engine inefficiency: pumping losses caused by restricting intake passage by the throttle plate that regulates air feeding the cylinders.[2]

Fiat S.p.A., now known as Stellantis, launched MultiAir in 2009, employing a proprietary electro-hydraulic system to precisely control air intake without a throttle valve[3] to increase engine power and torque, reduce fuel consumption, reduce emissions, and improve engine operation, offering "a more controllable flow of air during the combustion cycle in comparison with mechanical VVT systems."[4] The technology allows engines to be lighter and smaller while reducing pump losses. It can be adapted to existing engines by replacing the camshaft with the MultiAir system, thus requiring a new head only.

MultiAir was licensed to the Schaeffler Group in 2011, which also markets the system as Uniair.[5] Schaeffler began supplying Uniair systems in 2017 to Jaguar Land Rover, branded as Ingenium technology.[6]

Compatible with both naturally aspirated and forced-induction engines, MultiAir technology was patented by Fiat in 2002 and was launched at the 2009 Geneva Motor Show in the Alfa Romeo MiTo.[7] 1.4 L MultiAir engines for global markets are manufactured in Termoli, Italy at the Fiat Powertrain Technologies factory and the FCA's Dundee Engine Plant (formerly of Global Engine Alliance's GEMA manufacturing branch), with critical systems manufactured and assembled by Schaeffler Group.[5]

In 2010, the 1.4 L MultiAir engine won the International Engine of the Year[8] as well as Popular Science's Best of What's New.[1] In the same year, the Fiat SGE engine (0.9 L turbocharged and 1.0 L naturally aspirated TwinAir units), also using MultiAir technology, was launched in the Fiat 500. It is produced in Bielsko-Biała, Poland. It was named Best New Engine in 2011.[9]

Both FIRE and SGE units are equipped with MultiAir and use indirect fuel injection.

The GME (Hurricane) and GSE (FireFly) MultiAir II engines, which use direct fuel injection, were first made available in 2016.

  1. ^ a b "Fiat's Multiair engine wins Popular Science Award". Popular Science via Allpar.com. November 17, 2010. Archived from the original on March 3, 2016. Retrieved May 31, 2016.
  2. ^ Mark Gillies (October 2009). "Fiat's Multiair Valve-Lift System Explained". Car and Driver.
  3. ^ "Best new engine 2010". "International Engine of the Year". Archived from the original on 2012-06-30. Retrieved 2010-09-15.
  4. ^ Mike Hanlon (March 7, 2009). "Fiat releases MultiAir engine technology – is this a fundamental internal combustion engine design breakthrough?". Gizmag.
  5. ^ a b David Zoia (March 7, 2011). "Schaeffler Expects Other Takers for MultiAir Technology". Wards Automotive. Archived from the original on August 6, 2016. Retrieved May 30, 2016.
  6. ^ springerprofessional.de: Drivetrain | UniAir Valve Control for Ingenium Petrol Engine | springerprofessional.de, accessdate: 27. January 2018
  7. ^ "「MultiAir」 is launched on the Alfa Romeo MiTo". alfaromeopress.com. Retrieved 2009-06-18.
  8. ^ "Fiat's 1.4-liter turbocharged Multiair powerplant wins "Best New Engine of 2010" award". green.autoblog.com. Retrieved 2011-01-22.
  9. ^ "Fiat 875cc TwinAir". ukipme.com. Archived from the original on 2013-02-05. Retrieved 2012-01-03.