<P> Energy provided for the turbine work is converted from the enthalpy and kinetic energy of the gas . The turbine housings direct the gas flow through the turbine as it spins at up to 250,000 rpm . The size and shape can dictate some performance characteristics of the overall turbocharger . Often the same basic turbocharger assembly is available from the manufacturer with multiple housing choices for the turbine, and sometimes the compressor cover as well . This lets the balance between performance, response, and efficiency be tailored to the application . </P> <P> The turbine and impeller wheel sizes also dictate the amount of air or exhaust that can flow through the system, and the relative efficiency at which they operate . In general, the larger the turbine wheel and compressor wheel the larger the flow capacity . Measurements and shapes can vary, as well as curvature and number of blades on the wheels . </P> <P> A turbocharger's performance is closely tied to its size . Large turbochargers take more heat and pressure to spin the turbine, creating lag at low speed . Small turbochargers spin quickly, but may not have the same performance at high acceleration . To efficiently combine the benefits of large and small wheels, advanced schemes are used such as twin - turbochargers, twin - scroll turbochargers, or variable - geometry turbochargers . </P> <P> Twin - turbo or bi-turbo designs have two separate turbochargers operating in either a sequence or in parallel . In a parallel configuration, both turbochargers are fed one - half of the engine's exhaust . In a sequential setup one turbocharger runs at low speeds and the second turns on at a predetermined engine speed or load . Sequential turbochargers further reduce turbo lag, but require an intricate set of pipes to properly feed both turbochargers . </P>

Where is the turbo located on a car