The Practical Application and Effects of a Variable Event Valve Timing System

930825

03/01/1993

Event
International Congress & Exposition
Authors Abstract
Content
In order for automotive engine performance to meet the requirements of maximum power called for by the OEM sales department together with the increasingly punitive legislative demands of reduction in exhaust emissions and fuel consumption, it will be necessary to incorporate a number of additional performance enhancement devices in the engine designs of the near future.
Significant amongst these devices are Variable Valve Timing (VVT) mechanisms, which fall generally into three categories: Variable Phase Systems (VP), Variable Event Timing Systems (VET), Variable Lift and Timing Systems (VLT).
The competent application of a VVT system will result in: Reductions in low speed/load exhaust emissions, Reductions in idle speed, Reductions in low speed/load fuel consumption, Increases in low speed torque, Conservation of high WOT specific power output. This paper describes the engine design refinements required to fit a VET System into a number of cylinder heads, with direct acting cam followers and finger followers and discusses the improvements in fuel consumption, emissions and torque obtained by applying VET to a twin cam gasoline engine.
Meta TagsDetails
DOI
https://doi.org/10.4271/930825
Pages
12
Citation
Lancefield, T., Gayler, R., and Chattopadhay, A., "The Practical Application and Effects of a Variable Event Valve Timing System," SAE Technical Paper 930825, 1993, https://doi.org/10.4271/930825.
Additional Details
Publisher
Published
Mar 1, 1993
Product Code
930825
Content Type
Technical Paper
Language
English