SummaryThis paper presents the aerodynamic/mechanical design, development and testing of a turbocharger centrifugal compressor designated the C100. The compressor was designed for application to a range of passenger car diesel engines of capacity 2.2 - 2.5 litres.The main objective of the design was to supply a compressor which would meet the requirements of increased engine power and increased engine operating range. This must be achieved whilst improving the aerodynamic performance, reliability and durability of the compressor.The aerodynamic analysis of the blade shape was undertaken using a streamline curvature computer program and a 3D Navier-Stokes computer program. The mechanical analysis of the wheel was undertaken using a finite element computer program. The development and testing of the compressor was undertaken on an automated gas stand.The C100 has resulted in a production viable high performance centrifugal turbocharger compressor which can be used for passenger car diesel engines.