APR is pleased to present the ultimate transmission control unit (TCU) upgrade for the S6 and S7 DL501 DSG and S Tronic transmissions! APR’s TCU upgrade is conveniently flashed to the vehicle’s TCU through the OBD-II port with user definable options selectable at the time of install.
APR’s TCU upgrade goes beyond the overly simplistic norm of raising a few limiters, and offers a wide gamut of changes designed to enhance the driving experience especially when combined with APR’s performance engine software and hardware. With an in-depth knowledge of the transmission’s inner workings and control strategies, APR’s engineers have improved many aspects of the transmission from accelerative performance to daily drivability, while also incorporating new features including several typically reserved for higher-end Audi Quattro GmbH RS models.
*APR’s DirectPort Programming suite allows the end user to tailor the TCU upgrade to their needs at the time of installation.
APR’s calibration experts found the factory drive and sport modes to be less than ideal when raising power above the factory limits. In drive mode, the transmission aggressively seeks sixth gear, earlier than necessary, leaving behind an anemic and lack luster experience for the driver. Likewise sport mode leaves a lot to be desired considering its seemingly exciting name. Under both modes, maximum shift points remain optimized for the factory power levels, which vary greatly to those produced using APR’s world-renowned catalog of performance hardware and software. As such, accelerative performance suffers due to non-optimized shift points.
To rectify this situation, APR’s engineers took a multi-step approach to custom tailoring the shift maps to sync harmoniously with APR’s performance upgrades and each platform’s gear-ratio configurations. While some may simply set wide-open-throttle, or WOT shift points to the vehicle’s max RPM limit, APR’s engineers chose shift points based on actual acceleration data. This result is gear dependent shift points typically below the engine’s max speed, but in doing so, the vehicle’s acceleration improves as axle torque is matched before and after shifts.
Under low-torque, low-rpm, part-throttle situations, both modes less aggressively seek the highest possible gear. Drive still has the benefit of economy, but stays within the power band more comfortably for a more enjoyable experience. Likewise sport mode has been optimized to provide a sporty feeling, worthy of its name. In both cases, the transmission seamlessly integrates with APR’s performance upgrades to provide an exciting driving experience.
APR’s user definable options allow the end user to configure how the transmission works while the gear selector is placed in manual mode.
The kick-down switch, which is responsible for an instant downshift, is enabled by default but can be disabled at the time of install. Likewise the auto upshift that occurs at the vehicle’s maximum engine speed can also be disabled at the time of install, allowing the engine to bounce off the limiter like a manual transmission.
The transmission does not lock out any manual downshifts so long as the shifting does not result in an engine RPM above the max shift point. In all situations, paddle delay is reduced, allowing for a more responsive shift to take place and furthermore, shift times have been optimized.
APR’s 3-Step launch control is unlike anything else in the market. At the time of flashing, the user chooses a maximum launching RPM. When activating launch control, up to three launching RPM’s are available, allowing the end user to choose the best launching RPM based on the current conditions!
At 100% throttle with the kick-down switch engaged, the vehicle will select the highest launching RPM. At 100% throttle with the kick-down switch not engaged, a lower launching RPM is activated. Finally, at roughly 50% throttle the transmission chooses the lowest launching RPM. When properly dialed in, the user is left with incrementally higher launch points ideal for the street, track and sticky tires.
Utilization of launch control results in the transmission entering the maximum acceleration mode. During this mode, intervention between a shift is minimized, resulting in faster acceleration that keeps the driver planted to the back of his or her seat. The delay typically present after lifting the brake and beginning of the physical launch has been improved for a more immediate response.
Note: Both ASR and ESP must be fully off and the vehicle in Sport Mode to use Launch Control. This is accomplished by holding the traction control button for a length of time.
Temperature management is an important part of the DL501 transmission. While some may simply remove temperature protection routines all together, or mistakenly raise temperature protection torque limiters sky high and claim increased cooling performance due to zero transmission intervention, APR’s TCU upgrade only allows the maximum safe temperature levels before intervention. Under high stress scenarios, such as launch control, the transmission’s cooling pump runs at maximum speed until the desired transmission temperature is achieved.
Unlike the factory intervention routine, which allows for nearly no torque to be transmitted through the transmission at all after limits are crossed, APR’s over temp intervention allows for a limited amount of torque, enough so the vehicle can be safely driven off the track or pulled to the side of the road during intervention. In keeping the vehicle moving, airflow continues across the radiators, which in turn keeps coolant temps low and aids in removing heat from the factory DL501 oil coolers to restore full operation.
