Technical Paper
An Assessment and Comparison of De-Throttling Approaches and Technologies for Further Reductions in Fuel Consumption in a Modern GDI Engine
2017-10-08
2017-01-2224
The paper outlines the fuel consumption benefits available from de-throttling technologies that can help to bring gasoline engine efficiency on a par with that of diesel engines. The paper shows the relative efficiency improvements offered by a fully-variable intake valve lift system in conjunction with wide-range cam phasers, which also incorporate the facility to provide zero valve lift to enable cylinder deactivation. Testbed results recorded with a prototype concept engine show the degree to which early intake valve closing, valve overlap and cylinder deactivation can work together, and the limitations of this synergy at different operating conditions.
