BorgWarner Turbo & Emissions Systems

Turbocharger with R2S® Regulated Two-Stage Technology

Turbos have been available on passenger cars since the ‘60s, and twin turbos with their reduced turbo lag and high output have been installed on heavy duty trucks and a few high performance passenger cars since the ‘70s and ‘80s, but the benefits of such two-stage systems were greatly undermined by increasingly stringent emissions regulations, ungainly packaging, and performance robbing parasitic losses, to the point where they were virtually eliminated from modern engine designs.

BorgWarner Turbo & Emissions Systems overturned the conventional wisdom on twin-turbos with their R2S - Regulated Two-Stage Turbo system – to produce a compact assembly that addressed all the twin turbo issues. The R2S boosted an OEM’s abilities to reduce engine sizes, reduce emissions, increase performance, and improve fuel economy, all at once.

Available in fixed and variable geometry configurations, BorgWarner’s R2S is the result of thirty years of turbo system experience combined with advanced modeling technologies. It solved the performance loss and packaging problems that had precluded the benefits of two-stage systems. R2S is distinguished as a PACE Award winner by the insight that the first stage low pressure turbo could take on added responsibilities beyond its traditional role of enhancing low RPM performance. BorgWarner made it possible to use it to improve the emissions performance at high RPM as well as at transitional throttle conditions. Beyond the R2S system itself, BorgWarner also recognized that packaging two turbos and their associated plumbing was a problem for OEM product and power train teams, given today’s crowded engine compartments. They engineered an effective approach to coordinating a vehicle-specific turbo development process into the OEM’s vehicle development program.

For recognizing the dual-role potential of the low-pressure turbo and solving the packaging and parasitic loss issues that have been barriers to dual turbos, BorgWarner is a winner for the Regulated 2-Stage turbo system. Since its introduction in 2005, R2S is dominating the committed 2-Stage turbo volume through the 2012 model year, including planned use by Ford, BMW, Mercedes-Benz, MAN, and International.