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Unitronic Performance Software - 8Y.2 (2025+) Audi RS3

Unlock the full potential of your 8Y.2 RS3 with Unitronic’s cutting-edge performance software!
Unitronic
Unitronic
ES#:
5506329
Mfg#:
8Y2RS3ECUNEW 8Y2RS3ECUNEW
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Unitronic Performance Software - 8Y.2 (2025+) Audi RS3

Starting at: $1550.00
SALE: 1550.00
Starting at: $1550.00
WAS: $1700.00 on 08-22-2026

This product was last offered at the strikethrough price on
08-22-2026


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Unitronic Performance Software - Stage 1+
Performance gains of +160-223 HP and +129-159 LB-FT of torque depending on fuel type
5506337 8Y2RS3S1PNE
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No Lifetime Replacement
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SAVE 11% $1400.00

This product was last offered at the strikethrough price on
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1250.00
Unitronic Performance Software - Stage 2
Performance gains of +130-237 HP and +121-165 LB-FT of torque depending on fuel type.
5506342 8Y2RS3S2NE
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SAVE 10% $1500.00

This product was last offered at the strikethrough price on
08-23-2026

1350.00

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UniFLEX - Flex Fuel For E85
The first to implement native, true, flex fuel code to the factory Bosch MG1CS163 ECU called UniFLEX.
4920411 8YRS3FFADD
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500.00

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UAF - Unitronic Advanced Features Add-On
(UAF) Add-On gives unparalleled levels of control for true adjustability directly from the driver’s seat.
5375310 8YRS3UAFADD
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250.00

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Unitronic UniCONNECT+ Cable (Cable Only, Tune Not Included)
This cable is not necessary with current tune configuration but can be used to swap fuel types and tune stages.
4362321 UH008-TLA
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This product is lifetime replacement eligible Lifetime Replacement
This product is backed by our
Lifetime Replacement Program! Read more here
164.99

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Product Details

Unitronic FLEX fuel enabled ECU Performance Software Calibrations are available for this platform allowing for seamless transitions between 100% gasoline to 85% ethanol and anything in between, without requiring an ECU reflash. This FLEX enabled Software is available for an additional fee and it covers all lower stages up until your highest purchased stage as well. UniFLEX Hardware (ES#4785773) is required in order to take advantage of these FLEX enabled calibrations. Please contact Unitronic or your local Authorized Dealer to learn more.

Unitronic Advanced Features (UAF) are also available for this platform. Thanks to proprietary ECU code, the Unitronic Advanced Features (UAF) Add-On gives unparalleled levels of control over Pops and Bangs, Launch Control Settings and Rolling Launch Control for true adjustability directly from the driver’s seat. If the vehicle is not equipped with UniFLEX, Unitronic's FeatureBox (ES#5424774) allows for seamless integration with the all-new UAF Control mobile app.

SFD filters must be unlocked before your ECU can be reflashed or data logs can be collected via the OBD2 port with UniCONNECT+. To learn more about SFD, check out or FAQ's at the link in the bottom of the description.

Features

Engineered with Strict Industry Standards
With over 10 years of experience with Bosch and Siemens engine management systems and calibrations, Unitronic is able to utilize its expertise, industry leading tools and equipment to ensure an optimal calibration; delivering maximum performance, while maintaining complete OEM-like reliability and drivability.

Extensively Tested Under Various Driving Conditions
Development begins using Unitronic’s in-house Maha Chassis dyno housed in an environmentally controlled cell; closely monitoring a plethora of operational data, utilizing industry leading calibration tools and resources. Beta calibrations are then tested in street and track scenarios, using multiple cars under various driving conditions. This engine calibration strategy ensures Unitronic Performance Software delivers maximum performance, OEM-like drivability and reliability anywhere in the world. Unitronic Performance Software is only released to its Clients once development is thoroughly completed in accordance to Unitronic’s strict standards.

Factory Safety Limiters Retained
OEM “fail safes” are retained within the ECU calibration. Close monitoring of all operation parameters ensures that engine operation stays within factory components limits, resulting in reliability.

Optimized Responsiveness, Smoothness, Drivability, and Comfort
Unitronic’s ECU calibrations are engineered to improve engine response and reduce low-end lag. Unitronic’s Performance Software has gained worldwide recognition and is well known for its broad powerband, with smooth power delivery, maximizing responsiveness and “area under the curve”, under normal and hard acceleration.

Optimized Maximum Output
Unitronic’s ECU Calibrators deliver the maximum power output while staying within the operational limits of the factory engine and drivetrain components. Specifically, this results in the highest engine performance without sacrificing the reliability of the engine, turbocharger, or other engine and drivetrain components.

Power Delivery Perfectly Optimized Throughout the Power Band
Aligned with the OEM strategy, the calibration is designed to offer a large flat torque plateau to provide a smooth and linear power band. Maximum torque output is achieved sooner and maintained longer which creates a broader torque plateau and greater area under the curve. This results in an improved acceleration and optimal engine operation.

Improved Fuel Efficiency
Optimized timing and injection in cruising condition allows for an improved fuel efficiency, under normalized driving conditions.

Ignition Timing Precisely Calibrated for Higher Octane Fuel
Engine calibration optimized to take advantage of higher fuel quality to extract maximum energy from the combustion. Therefore, when using a higher octane fuel, more power and better fuel efficiency will be achieved.

Speed Governor Removed
Vehicle speed limiter within ECU is removed. (Subject to transmission rotational speed limit.)

Unitronic Stage 1 Performance Software is precisely calibrated for use with 91 octane / 95 RON fuel.
Performance Software for your ECU Box Code is subject to availability.
2025+ models require to have the hood opened during the flashing process.

Required Hardware

  • Unitronic MPI Injector Upgrade Kit (ES#4362302)
  • Unitronic UniFLEX Hardware Kit (ES#4785773) 
    • UniFLEX Hardware Kit and MPI Upgrade only required if using UniFLEX or E85 Software.

Recommended Hardware

  • Unitronic 4 inch Forged Carbon Fiber Intake System (ES#4772427)
  • Unitronic 4 inch Intake System (ES#4362366)
  • Unitronic 4-inch Turbo Inlet Elbow (ES#4920251)
  • Unitronic 5-Inch Intake System (ES#5435441 or ES#5435442)
  • Unitronic 5-Inch Intake System w/ Air Guide (ES#5435443 or ES#5435445)
  • Unitronic Intercooler (ES#4365190)

* SFD Filters Information: https://www.getunitronic.com/faq#whatissfdorsfd2andhowdoesitaffectinstallingperformancesoftware

Not for sale or use in the state of California on any pollution-controlled vehicle as per the California Air Resources Board.

This Part Fits the Following Vehicles

Make Model Submodel Engine Special Fitment Notes
Audi 8Y RS 3 Quattro 2.5T Use vehicle selector to confirm fitment
*The above product applications have been written by ECS Tuning. All warranties, product application, fitment, and performance are the responsibility of ECS Tuning. For additional information see the terms of use.
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