Unitronic's 3” Turbo Inlet Elbow for the 2.5TFSI EVO (EA855) engines, found in the 8V.2 RS3 and 8S TTRS, is made from aircraft grade cast Aluminum and is engineered as a direct bolt-on upgrade for the stock frame Borg Warner turbochargers that produces gains of +18HP / +8 LB-FT TQ and increases airflow by 12% through eliminating airflow restrictions and significantly improving overall turbo efficiency.
As is with all of its performance products, Unitronic utilizes only the latest industry leading tools, equipment, and computer aided design software that is packed with the latest technology from our technology partners at Creaform® and Stratasys®. These tools and technology help to achieve a design that not only optimizes airflow and speed, but also eliminates airflow restrictions that are present with the factory piece, while fitting within the engine bay constraints, and offers direct compatibility with the factory intake and many aftermarket intakes that are presently on the market, without needing any adapters, additional couplers, or other accessories.
Unitronic began with 3D scanning the 2.5TFSI EVO engine bay and OEM components with it’s in-house 3D scanner. Once 3D scan data has been collected and processed, Unitronic’s Hardware Engineers then interact with the 3D models to identify fitment constraints, mounting locations, other component locations, etc. to ensure the final product fits perfectly within the “envelope”.
Overall product design proceeds through, not only focusing on increasing overall performance of the product, but also the small and often overlooked aspects of the product’s design and function are of utmost importance to Unitronic. In this case, Unitronic’s Engineers worked on optimizing the air speed at the compressor inlet, just as Audi’s Engineers did, as cited in their published literature. As you can see in the comparison examples, air speed at the compressor wheel shows a relative uniform velocity profile across the opening.
Audi® Engineering Technical Diagram
Unitronic Turbo Inlet Elbow Speed at Compressor Inlet
Once initial designs are finalized, the next step is the rapid prototyping phase, utilizing its in-house Stratasys 3D printer. Within hours, Unitronic Engineers are able to have a complete working 3D printed rapid prototype, allowing for test fitments to be performed on the vehicle, functional testing to be completed, and flow data extracted to further validate the designs.
Using its in-house Superflow SF-1020 Flow Bench, Unitronic Hardware Engineers further validated designs to ensure that the Unitronic Turbo Inlet effectively optimizes airflow in a variety of conditions. The OEM inlet yielded a peak flow rate of 581 CFM at 28” of H2O, while the Unitronic 3” Turbo Inlet Elbow achieved 652 CFM, for a gain of 12% over the OEM inlet.
Pressure Differential (PSIA) @ 28inAq Air Velocity (Mach) @ 28inAq
Extra attention was spent to allow for a complete one-piece design including CNC-machined inlet and outlets, a fully integrated PCV routing with CNC-machined connection flange, and an ultra-smooth, flow-matched ariflow transition into the turbocharger.
Mostly importantly and in keeping consistent with the factory emissions and PCV system, Unitronic’s fully integrated PCV routing functions as it was originally intended by Audi’s Engineers responsible for designing the 2.5TFSI EVO EA855 engine. A pressure plot of the PCV exit shows that is has been positioned for optimized functionality.
Through the elimination of upstream [pre-compressor] restrictions, Unitronic’s new 3” Turbo Inlet Elbow improves the efficiency of the factory Borg-Warner turbocharger and is compatible with many stock frame hybrid turbochargers, including the TTE625, TTE700, and SRM GTX35.
Using its in-house MAHA LPS3000 Chassis Dyno, Unitronic performed back to back dyno tests using its 2018 (8S) Audi TTRS. This vehicle was using pump gas and was equipped with Unitronic’s upcoming Stage 2 93oct (98ron) Performance Software, Intercooler Upgrade, and Intake System, being otherwise completely stock. Unitronic’s 3” Turbo Inlet Elbow for the 2.5TFSI EVO EA855 produced a gain of +18 HP / 8 LB-FT of torque compared to the stock unit, without any changes in the Stage 2 ECU calibration, on the same vehicle, same day, within the same hour, maintaining the same environmental conditions inside of the dyno cell.