APR is pleased to present the TT RS 2.5 TFSI Stage III GTX Turbocharger System!
In the 1980s, an iconic legend was born as the world fell in love with Audi’s 5-cylinder engine’s unmistakable and intoxicating growl. To the Audi enthusiast, the light-weight, compact 5-cylinder engine represented the hallmark of Audi’s technical prowess and ability to emotionally captivate an audience with a driving experience unlike any other in its time. Audi’s announcement of the return of its 5-cylinder roots via the 2.5 TFSI sent shockwaves across the community and resonated deeply within the hearts and minds of APR’s staff. With this creation, Audi spoke directly to every enthusiast and gave APR the unique opportunity to write into Audi’s 5-cylinder history books with modern day engineering expertise.
APR’s technical reach has grown enormously since opening in the 1990s and currently represents a force of unmatched performance without compromise within the performance enhancement sector for Audi vehicles. The APR Stage III 2.5 TFSI Turbocharger System is a culmination of roughly two years worth of engineering research, development and motorsport testing unheard of in the market today. With brutal testing on multiple continents, including wins in the prestigious German Tuner GP at the Hockenheim ring, the APR Stage III Turbocharger System is the pinnacle of Audi’s German engineering enhanced by APR’s American ingenuity.
The APR Stage III Turbocharger System is a turnkey solution designed to expand on the TT RS’s already stellar performance by increasing peak horsepower to roughly double that of the European model. Sitting at 665 horsepower and over 560 ft-lbs of torque on high octane fuel, the vehicle’s performance is transformed to that of a modern day equivalent of Audi’s motorsport 5-cylinder engines of yesteryear. APR’s advanced knowledge of engine management combined with an uncompromising selection of premium materials, access to the latest engineering equipment and techniques, as well as a highly educated and capable staff of engineers, resulted in a turbocharger system capable of delivering a truly exhilarating and fulfilling driving experience.
APR's engineering teams use professional grade tools to aid in development of the APR Stage III Turbocharger System. Through the use of coordinate measuring machines, such as the Creaform 3D laser scanner and FaroArm, spatial constraints within the 2.5 TFSI's engine bay were captured to give APR's engineers a detailed map of their design environment. The 3D laser scanner allows for quick and easy modeling of static hard parts, such as the turbocharger unit. The modeled parts are placed within the mapped engine bay and development on the system begins using PTE's Creo 2 3D CAD software. With such an unforgivingly tight working environment, this data is absolutely necessary to ensure every parts fits as intended.
Unfortunately an engine bay is not a fixed working environment. Under load the engine mounts allow for movement, ultimately changing and limiting the spatial constraints even further. Before production hardware is created, APR's engineers print each part using an in house sterolithography 3D printer. Fitment is then tested and necessary changes are made before casting the final pieces.
Over the entire development period, APR's Calibration and Electrical Engineering teams continued modifying the factory engine management system to provide a smooth and reliable driving experience. Particular attention was paid towards driving characteristics, ultimately increasing the responsiveness of the entire system through the reduction of turbocharger lag. Given that the system operates at such high levels of performance, it's often outside of the scope originally intended by the factory ECU. As a result, APR’s Electrical Engineers added patented control strategies to the ECU to enable proper control in all situations.
Success of the system depended greatly upon the results of APR's accelerated life testing. APR's in-house TT RS as well as select APR Importers' vehicles from across the globe were chosen for their locations in harsh environments. From the Swiss Alps to the South African deserts, APR’s engineers spent over a year collecting data through normal daily driving and grueling motorsport events. As new design requirements arose during testing, changes were made and testing continued. The end result is an extremely powerful, yet reliable turbocharger system worthy of APR's stamp of approval.
More than a year before release, APR gave The Drive Network's Matt Farah access to the vehicle for early developmental feedback. At the time, the vehicle was producing less power than available today, but still offered a thrilling experience. See what Matt had to say in the video below.
At the heart of the APR Stage III GTX Turbocharger System is a GTX3576R turbocharger, utilizing the latest technologies from Le Mans winning turbo manufacturer, Garrett Honeywell. The turbo features a fully-machined, eleven-blade billet compressor wheel and a dual ball bearing oil and water-cooled CHRA. APR's Engineers spent countless hours testing several turbocharger units to arrive at a configuration suitable for their power, reliability and drivability requirements. Testing began with smaller internally gated units and gradually increased over time until a balance was met within all categories. The result is a system that spools quickly with excellent response, even in the lower RPM range, while producing top end power figures beyond that of a Audi R8 LMS Ultra V10 FSI!
Each turbocharger unit is assembled and clocked in-house at APR with the necessary components to ensure proper fitment and orientation for compressor inlet and outlet systems as well as all oil and coolant lines.