The regulated two-stage (R2S) turbocharger features a water-cooled compressor housing and consists of two series-connected turbochargers of different sizes to deliver high boost pressures and smooth power over the entire engine speed range, says BorgWarner.
One turbocharger features the company’s variable turbine geometry (VTG) technology for the high-pressure stage combined with a larger B03 water-cooled turbocharger, which is optimised for low-pressure exhaust gas recirculation. Controlled by an electric actuator, the VTG turbocharger responds quickly at low engine speeds, resulting in a rapid rise in boost pressure. As engine speed increases, a bypass gradually redirects the exhaust gas flow towards the larger, low-pressure turbocharger until it takes over the workload completely.
The R2S is fitted to Jaguar Land Rover’s new 2.0-litre I4 diesel engine.