The use of turbochargers for gas and diesel engines is growing rapidly as demand for reduced energy consumption and emissions intensify. Turbochargers traditionally have been employed on large reciprocating engines and used for ship, locomotive, heavy truck, power production and mechanical drive applications. More and more, automotive manufacturers use turbochargers to improve efficiency and derive greater power from small engines. Small turbochargers use a radial inflow turbine to drive a centrifugal compressor; larger units use an axial flow turbine. In all cases, the objective is to improve efficiency and reliability over a very wide operating range. Package size is often a key constraint, particularly for automotive usage.