Performance Improvements for Connecting Rod Bearings with “End-Relief”

The constant engine development requirements of increased durability with lower cost, size and power loss need innovations in technology from designers and manufacturers of critical components such an engine bearings. A detailed experimental program has shown that a connecting rod bearing with “end-relief” grooves can give surprising and unexpected benefits in reducing bearing temperature. Bearing shells with “end-relief” resulted in an effective bearing width reduced by 6mm or 30%, yet still gave benefits in temperature reduction. The depth of the “end-relief” was too large for any hydrodynamic oil film to generate pressure to support the applied load.