Balance Shaft Conversion of a Four Cylinder Engine - The Challenges of Packaging and Mechanical Integration

The paper describes the addition of twin balance shafts to the Ford 2·3I DOHC 4-cylinder engine. The conversion of a production engine involves overcoming severe component packaging constraints. This is coupled with the need to ensure that the performance of existing engine systems, particularly lubrication, are not compromised, and the requirement to minimise disruption to current manufacturing processes.

The system achieved 92·5% balance of secondary forces - the maximum attainable within packaging and oil aeration constraints. A substantial improvement in vehicle noise, vibration and harshness was recorded.