APR Presents the B7 RS4 4.2L FSI V8 Stage III+ TVS1740 Supercharger System!
http://www.goapr.com/news/wp-content/uploads/2014/01/RS41740.png
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_kit.jpg
APR is pleased to present the B7 RS4 4.2L FSI V8 Stage III+ TVS1740 Supercharger System!
Since the release of the B7 RS4, Audi’s technological advances on RS models have grown dramatically. However, this often came along with the removal of traditional manual 6-speed transmissions many RS owners have grown to love. APR quickly realized the RS4 represented one of Audi’s last great performance sedans and chose to continue advancing the platform more than half a decade after the last RS4 rolled off the production line.
APR’s technical reach has grown enormously since opening in the 1990’s and currently represents a force of unmatched performance without compromise in the performance enhancement sector for Audi vehicles. Our previously available APR Stage III TVS1320 Supercharger System found its way on to several hundred RS4s around the world, making it the most popular and reliable system on the market. With more than four years’ worth of RS4 supercharger engineering research, development and testing, APR’s new Stage III+ TVS1740 Supercharger System represents the pinnacle of Audi’s German engineering enhanced by APR’s American ingenuity.
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_installed.jpg
In the factory form, Audi’s older high revving FSI V8 leaves much to be desired compared to some of the latest technological advances brought forth by Quattro GmbH in recent years. The APR Stage III+ TVS1740 Supercharger System fills the void by adding an average of roughly 40% more horsepower and torque across the entire power band. The results are nothing short of amazing; taking the RS4 from 414 horsepower to 626 horsepower on pump fuel and 688 on race fuel without breaking a sweat! With more than 500 FT-LBS on tap thanks to the TVS1740’s positive displacement supercharger expect instant acceleration with absolutely no lag commonly associated with other forms of forced induction.
APR Stage III+ TVS1740 Supercharger Components
Supercharger and Manifold
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_supercharger_mid.jpg
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_supercharger_bottom_mid.jpg
At the heart of the APR Stage III+ Supercharger System is Eaton’s latest Twin Vortices Series (TVS) supercharger unit, the TVS1740. The supercharger system is a positive displacement, roots style pump, utilizing Eaton’s lightweight, four-lobe 160 degree twisted rotors. Cast and assembled as a single, OEM-style-manifold and rotating group housing, the unit is quiet, compact, attractive, easy to install, and requires little to no extra maintenance to the unit itself.
The positive displacement supercharger offers power instantly as the throttle is pressed. Boost pressure builds with no perceived lag commonly associated with other types of forced induction, and provides a large increase in torque across the entire power band. Throttle control is linear and predictable and makes for an excellent driving experience both in daily driving and wide-open acceleration.
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_supercharger_front_mid.jpg
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_supercharger_rear_mid.jpg
Since the supercharger does not compress air as it moves through the roots, it’s extremely efficient during light throttle and cruising situations. Unlike screw-type positive displacement superchargers that are always compressing, the TVS unit can internally bypass unwanted air, resulting in negligible parasitic loss during cruising and thus far greater fuel economy.
The single cast unit and appropriately sized rotating group eliminates potential leak points and allows for a slim, compact design without sacrificing key airflow design characteristics. The unit features a high velocity flow path through the supercharger rotors and an unrestricted discharge port into the appropriately sized plenum. The large plenum equalizes flow across all ports as air feeds evenly through the low-pressure-drop, dual-internal air-to-water heat exchangers. Finally, the ports are separated into individual runners, offering greater operation by eliminating cross talk.
Internally the dual heat exchangers offer technological advances shared by Formula 1 teams around the globe. Each unit features a louvered fin design, which minimizes pressure drop while achieving excellent cooling effectiveness. The extruded multi-rib tubing maximizes heat extraction to be carried away through the large bore coolant recirculation hard lines. Externally, supercharger coolant is pumped through a large front mounted heat exchanger where it’s cooled and circulated back through the charger again.
Engine Management
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_ecus_mid.jpg
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_dyno_mid.jpg
The factory Bosch MED 9 engine management system is responsible for proper operation of the engine during constantly changing environmental and load conditions. With built in compensational data for environmental variables and varying load conditions, the factory ECU is far more complex and intelligent than units found in other vehicle makes and marques.
With the significant amount of changes included in the APR Stage III+ TVS1740 Supercharger System, APR’s Engineers spent months calibrating the engine management system, including well over 100+ hours of in-house chassis dyno development. Drivability, gear changes, cruising and part throttle operation were tuned to operate smoothly as if intended by the OEM. Further development was performed putting the vehicle through performance evaluation and durability testing at the drag strip. APR’s Electrical Engineers built new coding functions, strategies and routines into the ECU to control conditions normally unseen at factory power levels. Thanks to APR’s incredible proprietary calibration suite, data logging software and full access to the coding structure of the ECU, appropriate and intelligent changes are made to ensure flawless drivability and excellent performance without compromise.
Adding forced induction to a naturally aspirated engine presents several challenges with regards to how the ECU operates. APR’s Calibration Engineers properly restructured the engine’s volumetric efficiency (VE) model to properly determine the ECU’s calculated load. Accurate open loop fueling is achieved, translating to insignificant fuel trim adjustments. Closed loop fueling is calibrated to control lambda perfectly under all operating conditions. Furthermore, compensations, such as ones related to intake air temperature, are adjusted to handle the large temperature variances compared to a factory naturally aspirated setup.
APR’s Calibration Engineers have optimized cam timing, ignition timing and lambda to provide tremendous leaps in power while retaining OEM knock control sensitivity. The result is safely achieved power, optimized for various fuel grades found around the world from low quality pump fuel, all the way to high quality, oxygenated race fuels.
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_track_mid.jpg
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_road_mid.jpg
Beyond power and torque enhancements, APR’s Calibration Engineers were able to increase the acceleration rate of the vehicle through other calibration changes. Ignition delays are reduced resulting in a more responsive pedal without altering overall throttle sensitivity and resolution. Drivability was greatly improved by reducing the throttle lag commonly noticed at slow speeds and while reapplying throttle after decelerating. APR’s Motorsport Rev Limiter allows power to climb all the way to the factory set redlines without dropping off several hundreds of RPM earlier. And lastly, APR’s tried and tested 4,200 RPM Motorsport Launch Limiter allows the driver to focus on launching the vehicle, rather than controlling the engine speed.
Beyond wide open throttle performance, APR’s Calibration Engineers spent countless hours optimizing vehicle drivability under daily, part-throttle, driving. The vehicle’s pedal maps are recalibrated under both standard and sport mode, providing smooth part-throttle drivability without compromising the driveshaft windup protection. The vehicle fully retains its impressive daily driver status and simply has more power on tap should the driver request more with his or her right foot! We call it Performance Without Compromise.
Front Mount Heat Exchanger
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_fmhe_mid.jpg
APR’s supercharger system features a large, 310mm x 540mm x 42mm, front mount heat exchanger responsible for cooling coolant as it’s pumped out of the supercharger’s dual internal air-to-water heat exchangers. This is a critical component in any supercharged application to not only keep power consistent, pull after pull, but also to help keep IAT below dangerously high levels. The heat exchanger is specific to the RS4 platform, featuring a hand welded design and CNC, laser-cut brackets to provide a simple and clean method of mounting to the vehicle.
Coolant Pump and Harness
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_coolant_pump_mid.jpg
APR’s coolant pump connects to the supercharger coolant circuit and continuously circulates coolant through the supercharger’s dual internal air-to-water radiators and APR front mount heat exchanger. The pump provides adequate coolant flow through a system of this size. The pump seamlessly connects to the factory wiring harness through the included APR wiring harness with no wire splicing and is triggered by the included relay system. APR’s CNC, laser-cut bracket provides a simple and clean method of mounting the pump to the vehicle.
High Pressure Fuel Pumps
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_hpfps_mid.jpg
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_hpfp_internals_mid.jpg
Sold separately as brand new pumps or rebuilds of the engine’s existing pumps, the APR High Pressure Fuel Pumps address fueling needs and leaves plenty of headroom for safety and further increased power levels. By increasing the pump’s internal capacity, the fueling system is capable of displacing a higher volume of fuel per minute at every RPM. Read more on our APR High Pressure Fuel Pumps product page.
Coolant Expansion Tank
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_coolant_expansion_tank_mid.jpg
The APR coolant expansion tank is used for filling the supercharger’s cooling circuit and for handling liquid expansion under various operating temperatures. The tank is cut from a single block of aircraft grade 6061 aluminum billet, is anodized black and proudly displays the APR logo. APR’s CNC, laser-cut bracket provides a simple and clean method of mounting the expansion tank to the engine bay.
Throttle Body Hose and PCV Bracket
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_tb_hose_mid.jpg
A wire reinforced, multi-ply silicon hose is provided to connect the throttle body to the intake housing. The ultra-ridged design ensures the hose will not collapse under the tremendous vacuum created by the supercharger system’s forced induction. The hose is engineered to fit properly into the engine bay with the necessary ports securely affixed by OEM style crimp clamps.
A laser-cut, CNC-bent, PCV hose bracket with retained fasteners is provided to secure the factory PCV pipe to the repositioned throttle body.
Fueling Hardware
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_fueling_hardware_mid.jpg
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_rprv_mid.jpg
APR’s supercharger system varies greatly from the OEM intake manifold design, and for fitment’s sake, the factory high pressure fueling system must be modified. The fuel rails and other high pressure and low pressure direct injection fuel lines are replaced with new, low profile, OEM parts. All OEM safety equipment remains intact.
An APR high-pressure rail relief valve allows the system to operate at greater rail pressures, resulting in a reduction of injection on-time which translates to more ignition advance and greater power.
The kit also includes all new high-pressure fuel pump low-pressure fittings, replacement injector O-rings, and OEM style extension harnesses requiring absolutely no splicing of the factory harness.
Spark Plugs
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_plugs_mid.jpg
To cope with raised cylinder pressure and temperature, eight NGK Iridium IX spark plugs are included. The plugs operate at a heat range colder than stock, which results in better pre-detonation resistance under extreme conditions. With these spark plugs in, APR’s calibration engineers were able to safely achieve more power, especially in extremely demanding conditions.
Intake Air Temperature Sensor and Harness
http://www.goapr.com/includes/img/products/stage_3+_b7rs4_iat_sensor_mid.jpg
The factory mass airflow sensor includes an intake air temperature (IAT) probe and is designed to provide the engine control unit (ECU) with air temperature information. Because the RS4 is converted from naturally aspirated to forced induction, the sensor must be relocated to ensure proper IAT measurement. The IAT sensor is absolutely critical for safe, reliable and powerful operation and as such, APR provides an OEM sensor and harness for placement just past the supercharger’s dual internal air-to-water radiators. The included harness allows for simple integration into the OEM wiring harness.
The sensor feeds correct IAT readings to the ECU, which provides closed loop control over various calibration decisions, such as desired ignition advance. This provides safe operation no matter what the condition. During a cold day, with lower supercharger coolant temperature, the ECU will safely increase engine output mainly through ignition. However, under hot conditions, such as a vehicle seeing plenty of track time, the ECU will compensate for these conditions, lowering output slightly to avoid dangerous premature detonation. These compensations result in only attempting to safely achieve the maximum amount of power capable during any given temperature related scenario.
