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U.S. Department of Energy
Office of Scientific and Technical Information

Effect of some lubricant and engine variables on instantaneous piston and ring assembly friction

Book ·
OSTI ID:5856102

The Instantaneous IMEP method has been used to measure piston and ring assembly friction in a production Chevrolet 1.8 litre L-4 and a 5 litre V-8 engine modified for single-cylinder operation. Friction measurements are reported at different loads and speeds up to 1640 RPM under firing and motoring conditions with various oils and before and after break-in of the oil ring. Oils used were SAE viscosity grades 30, 50 and 30 with a friction modifier. Differences were found between motoring and firing friction, especially on the power and exhaust strokes. These differences diminished at higher speeds and lower loads where lubrication was more hydrodynamic. Differences in response to viscosity and friction modifier changes were noted between the two engines.

OSTI ID:
5856102
Report Number(s):
TP-840178
Country of Publication:
United States
Language:
English