Case Study | Audi RS Q8 (4M)

At PERON Automotive, we love the EA825 4.0 TFSI engine, and the Audi RS Q8 (4M) stands out with its blend of supercar-rivaling performance and luxurious comfort. Our project elevated this car from Stock to Stage 2, integrating high-performance components such as an Akrapovič exhaust, Nortech Performance downpipes, and an ITG panel filter to achieve 735 hp. With advanced ECU and TCU recalibrations, we optimised the vehicle's performance across all aspects, transforming the RS Q8 into a powerhouse that seamlessly merges executive sophistication with exhilarating drivability.

Collection | Audi RS Q8 (4M)

The Brief

The development brief for the RS Q8 was to build on our success with the RS 6 (C8) by implementing tailored upgrades for this super SUV. Our class-leading ECU and TCU calibrations transform this beast into a much faster, smoother car suitable for daily commutes and school runs, or weekend blasts across the Continent.

For enhanced auditory pleasure and additional power, we replicated the steps taken with the RS 6, adding an Akrapovič exhaust, Nortech Performance downpipes, and an ITG panel filter. The new software and hardware package gives the RS Q8 a split personality, being quiet and demure in Comfort mode before becoming loud and aggressive in Sport mode, all at the push of a button.

Our Results

This particular RS Q8 has progressed from Stock to Stage 2, resulting in excellent performance and superior sound characteristics with minimal hardware upgrades. Initial dyno runs, conducted with an Akrapovič cat-back exhaust under very hot ambient conditions, showed numbers close to a stock vehicle. The Stage 2 dyno runs, also performed in hot conditions, indicate that results could have been even better with upgraded intercoolers. Despite less-than-optimal conditions, we are pleased with the results.

The RS Q8 translates the solid dyno numbers into an exciting driving experience with strong power delivery and hard-hitting response. The improved driving characteristics enhance both usability and the fun factor, making the performance gains seem almost absurd in an SUV.

  • ~130 hp increase in maximum power
  • ~241 lb-ft increase in maximum torque

Establish Baseline and Identify Areas for Improvement

Our first step towards any transformation is to test the vehicle both on our in-house DynoJet 424x linked dyno cell and on the road. This evaluation serves to establish a baseline of the car’s performance capabilities and gives us a feel for what is needed to improve the driving experience. By assessing the vehicle under controlled conditions and real-world scenarios, we identified a few areas for improvement. We discovered the RS Q8 drives similarly to the very familiar Audi RS 6 (C8) and required a similar upgrade path.

The air intake system was better than the RS 6 but still left much room for improvement. The exhaust system was too restrictive and muted the engine’s potential sound. The factory gearbox calibration had conservative limits and shift strategies that inhibited the engine's capabilities without being smooth. The factory engine calibration left a lot of potential untapped. Addressing these areas of the drivetrain was essential to transform the RS Q8 into a true super SUV that rivals the performance of more exotic machinery while maintaining the luxury expected of a big Audi.

Performance Parts

We strategically selected performance upgrades to safely increase power and improve the vehicle's acoustic profile. The upgrades began with an ITG Panel Filter in the factory airbox, which reduces pressure drop in the turbo inlets to improve air delivery and engine responsiveness. To ensure ignition efficiency, a new set of NGK spark plugs with an optimised gap was installed, providing consistent ignition performance at increased power levels.

The exhaust system saw significant enhancements with Nortech Performance large diameter downpipes, designed to reduce backpressure and enhance exhaust flow. This reduction improves turbocharger efficiency and moves heat away from the engine compartment. The downpipes are mated to an Akrapovič Evolution Line exhaust system, which provides an aggressive but tailored sound, improved exhaust flow, and reduced weight. These performance hardware upgrades work in synergy with the ECU and TCU calibrations to create a complete package that is greater than the sum of its parts.

Engine Control Unit Calibration (ECU)

To unlock the full potential of the Audi RS Q8 with its upgraded components, we optimised the engine ECU calibration. Fuel delivery adjustments ensured optimal rates for the increased air intake and exhaust flow, facilitating efficient combustion at higher power levels. Ignition timing was precisely fine-tuned to match the enhanced airflow and fuel mixture, maximising power output and preventing knock or pre-detonation while maintaining factory safety margins, which is critical when running on 99RON fuel.

Turbocharger control system modifications allowed for higher boost levels, significantly increasing power without exceeding safe operating limits for the turbocharger or engine. Torque output curves were recalibrated to provide smoother power delivery across a broader RPM range, enhancing both performance and drivability. An optimised cooling strategy was used to maintain ideal engine temperatures, ensuring consistent performance under various driving conditions. Additionally, engine RPM and vehicle speed limits were adjusted to give a broader range of performance for both daily and spirited driving scenarios.

Transmission Control Unit Calibration (TCU)

The transmission control unit (TCU) calibration was refined to complement the upgraded engine performance of the Audi RS Q8. We recalibrated shift points to ensure they align perfectly with the enhanced torque and power curves, resulting in smoother and faster gear changes. By increasing the torque limits and optimising the hydraulic pressure, we improved the gearbox's ability to handle the increased power output without compromising reliability.

Furthermore, adjustments were made to the shift strategies in various driving modes. In Comfort mode, shifts are seamless and refined, enhancing the daily driving experience. In Sport mode, the shifts become more aggressive, providing quick and precise gear changes that contribute to the vehicle's exhilarating performance. These TCU calibrations ensure that the RS Q8 offers a versatile driving experience, seamlessly transitioning from a luxurious SUV to a performance powerhouse at the push of a button.

Future Upgrades

This RS Q8 is currently at the Stage 2 level, equipped with an ITG panel filter in the airbox, Nortech Performance downpipes, and an Akrapovič Evolution Line exhaust system. The next step is to add upgraded intercoolers for better performance consistency under extreme conditions. For improved intake flow and aesthetics, an Eventuri carbon intake is planned to round out the upgrades from Stage 2 to 2+.

The Stage 3 upgrade includes TTE1020 turbos and 4 bar MAP sensors, a package proven through our collaboration with QST on the record-setting RS 6 (C8), and easily adaptable to the 4M chassis.

Please get in touch if you would like to discuss upgrading your Audi RS Q8 (4M).

Contact PERON Performance

With years of experience across a wide range of applications, PERON Automotive is at the forefront of VAG tuning. Our approach is characterised by a narrow and deep focus on these platforms, combined with an unwavering obsession for excellence. Leveraging our advanced research and development centre, complete with an in-house dyno, we lead, validate, and support the performance aftermarket.

Partnering with the global best in ECU/TCU tuning and performance hardware, including our in-house Nortech Performance division, we deliver comprehensive tuning solutions that are proven both in our facilities and on the track. Contact PERON to discuss your upgrade path and learn more about how we can transform your vehicle.

Tuning Advisor