Low-tension piston rings and roller cam follower for engine friction reduction - costs of retooling and fuel-economy benefits. Final report

Technical Report · Mon Aug 01 00:00:00 EDT 1988

OSTI ID:5121139

Thur, G M; Paterson, D J; Reilly, D

Automobile manufacturers recognize that two major sources of friction losses in automobile engines are the cam-lifter interface and the piston-ring interface in each cylinder. In city driving, friction may consume 20 to 30% of the available fuel energy. Perhaps 50% or more of the engine friction in city driving is from the piston rings and 25% is from the conventional valve train containing a flat face follower. Some recent gasoline-engine designs have incorporated roller lifters and lower-tension rings resulting in energy reduction and improved fuel economy. A methodology for estimating these improvements is presented by two case studies. For the range of conditions assumed in the study, the composite fuel-economy gains for both roller followers and low-tension rings ranged from about 3.25% to 5.16%. The low tension rings have no cost penalty, but they must be designed for adequate sealing, low blowby and good oil consumption. The roller followers and required cam improvements vary in cost depending on the valve-train design. The cost to the customer will be about $25 to $35 for a four-cylinder and $45 to $50 for a six-cylinder engine. The details of the methodology and costing are discussed in the report.

• Research Organization: Chi Associates, Inc., Arlington, VA (USA)
• OSTI ID: 5121139
• Report Number(s): PB-90-115676/XAB
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
AUTOMOBILES
INTERNAL COMBUSTION ENGINES
FUEL ECONOMY
PISTONS
TRIBOLOGY
COST BENEFIT ANALYSIS
DESIGN
ENERGY EFFICIENCY
FRICTION
FUEL CONSUMPTION
PROGRESS REPORT
DOCUMENT TYPES
EFFICIENCY
ENERGY CONSUMPTION
ENGINES
HEAT ENGINES
VEHICLES
330700* - Advanced Propulsion Systems- Emission Control
320303 - Energy Conservation
Consumption
& Utilization- Industrial & Agricultural Processes- Equipment & Processes