2021–2025 Audi A4 / A5 45 TFSI Stage 1+ E85 ECU Tune (B9.5 Hybrid EA888)
Boost Dynamic Tuning • Full E85 / Flex Support • OBDII Remote Flash

Unleash the Full Potential of Your 2021–2025 Audi A4/A5 45 TFSI (B9.5)

Exclusively Tuned by Boost Dynamic Tuning — The Only USA-Based Solution

If you own a 2021+ Audi A4 or A5 45 TFSI with the hybrid EA888 2.0T (B9.5), you’re holding untapped power — and we’re the only USA-based tuner with a proven solution for this platform. At Boost Dynamic Tuning, we don’t follow the crowd — we lead it. Our Stage 1+ E85 ECU calibration is engineered specifically for the B9.5 hybrid setup, and no one else in the country offers what we do.

With 11+ years of calibration experience and fully in-house development, we don’t rely on “theoretical gains.” Every file is backed by real-world logging and dyno validation — no smoke, no mirrors, no additives. Just clean, repeatable power you can feel every pull.

Why Choose BDT?

• Exclusivity: The only USA-based tuner offering a tested Stage 1+ E85 solution for the B9.5 hybrid platform.
• Authenticity: Built and refined in-house — no resellers, no recycled maps.
• Transparency: Real before/after dyno and road data.
• Remote Convenience: Flash at home through the OBDII port — no shop visit required.

This isn’t just tuning — it’s engineering with passion, for people who demand more from their Audi.

Fitment & Compatibility

• Models: Audi A4 45 TFSI / Audi A5 45 TFSI
• Years: 2021, 2022, 2023, 2024, 2025
• Chassis: B9.5
• Engine: Hybrid EA888 Gen 3 2.0T
• Fuel: E85 Required (Stage 1+ E85 calibrated)
• Tuning Method: Remote OBDII Flash (At-Home)
• Downpipe: Not required / not compatible on this platform

BDT Stage 1+ E85 Power Gains

Ethanol gives the EA888 hybrid a totally different personality — cooler temps, higher octane, and more timing headroom. Stage 1+ E85 is the sweet spot for drivers who want a major jump in performance without heavy hardware changes.

Unleash up to 330 WHP / 380 WTQ on E85.

BDT Stage 1+ E85 Highlights

• Full E85 Stage 1+ calibration with refined ethanol boost & torque strategy
• Optimized boost and torque delivery for stronger midrange and top-end
• Intake Air Temp Safety alert (dash warning when pushing too hard)
• Speed limiter removed
• Torque limiters raised
• Raised rev limiter (Neutral/Park)
• Load limits raised
• Auto Start/Stop defaults OFF (still functional)
• Crackle/Overrun in Dynamic mode only
• Calibrated stock boost gauge for higher readings
• Sharper throttle response & reduced turbo lag
• Increased LPFP & HPFP pressure strategies for ethanol fueling
• VVT recalibration
• Flashable via OBDII — no physical ECU mods required

Stage 1+ E85 Hardware Requirements

Fuel Note: This file is calibrated for E85 operation. Always verify ethanol content from a reputable station. If your area has inconsistent ethanol quality, contact us before flashing for guidance.

Remote Flash from Home (OBDII)

Flash your ECU at home through the OBDII port. We provide step-by-step instructions and remote support so you’re never guessing.

Remote Tuning How-To

Built for the Streets. Proven on the Dyno.

Whether you're carving through backroads or lining up at the next meet, Stage 1+ E85 gives your Audi the edge — with OEM+ drivability and hard-hitting torque when you want it.

Stop leaving power on the table. Elevate your driving experience with BDT’s Stage 1+ E85 tune — crafted exclusively for your 2021–2025 B9.5 Audi A4/A5 45 TFSI.

Crackle Pops / Overrun (Dynamic Mode Only)

Bring your Audi to life with our overrun/crackle calibration — a crowd-favorite feature that adds drama and personality to every drive.

When decelerating from higher RPMs or free-revving in Neutral/Park, you’ll hear sharp, exhilarating pops and crackles. It’s a controlled and safe enhancement designed to deliver an aggressive sound profile that turns heads — especially when paired with an aftermarket exhaust.

Note: Effect may be more subtle on stock exhaust systems. Safety logic reduces crackles if exhaust temperatures rise excessively.

⚡ Boost Control Optimization

The stock ECU often delivers an inconsistent boost curve, causing delayed throttle response and uneven high-load pulls. Stage 1+ E85 completely refines boost control for clean power.

• Smoother, more linear boost delivery
• Sharper throttle response
• Consistent power across the entire powerband

The difference is instant — predictable acceleration, no hesitation, just pure pull.

Customer Reviews + Live Phone Chat

Maintenance Schedule (Required for Tuned Vehicles)

IF YOU WANT YOUR CAR TO SURVIVE, THESE MUST BE DONE!

I want your car to survive multiple years with my tune. This isn’t a “nice to have” list — it’s what I’ve seen work over years of tuning EA888 cars. If you can’t afford the maintenance, please don’t tune the car. This is how you keep it reliable.

EMISSIONS COMPLIANCE NOTICE & LEGAL DISCLAIMER

FOR COMPETITION USE ONLY — NOT FOR STREET USE

This product is sold and intended solely for vehicles used in closed-course racing, off-road competition, or organized motorsport events. It is not legal for use on any pollution-controlled vehicle operated on public roads or highways, as defined under the Clean Air Act (42 U.S.C. § 7522) and applicable state emissions laws.

By purchasing, installing, or using this product, you explicitly acknowledge and agree to the following terms:

Federal and State Emissions Compliance

• This product may modify, bypass, defeat, or render inoperative one or more emissions control devices, including but not limited to: catalytic converters, oxygen sensors, EGR systems, or OBD monitoring systems.
• The installation or use of this product on any vehicle subject to emissions regulations is strictly prohibited by federal law and may result in civil or criminal penalties, including fines up to $45,000 per vehicle under the Clean Air Act.
• This product is not certified by the EPA or CARB, and is therefore not legal for sale or use in California or any CARB-aligned state.

Assumption of Risk and Waiver of Liability

By purchasing and/or installing this product, you agree to:

1. Assume all risk and responsibility for compliance with applicable emissions laws.
2. Waive all claims, liabilities, and legal actions against Boost Dynamic Tuning, LLC and affiliates arising from unlawful use.
3. Release Boost Dynamic Tuning, LLC from any damages or penalties resulting from improper or illegal use.

⚖️ Indemnification Clause

You further agree to indemnify, defend, and hold harmless Boost Dynamic Tuning, LLC from any fines, penalties, damages, losses, or legal fees resulting from:

• Use of this product in a manner inconsistent with this disclaimer
• Misrepresentation of vehicle use
• Violation of emissions laws or regulations

Final Notice

This product is sold “as is” and “with all faults”, with no warranties regarding legality for highway use or emissions compliance.

It is the sole responsibility of the end-user to determine the legality of this product for the intended application. Boost Dynamic Tuning, LLC does not condone or recommend illegal street use or emissions equipment tampering.

By completing your purchase, you acknowledge that you have read, understood, and agreed to this disclaimer in full.

** PLEASE NOTE: If you schedule an appointment to flash your tune and you are late with no contact, a $50 late fee applies. If you need to reschedule, contact us at least one hour before your appointment or a $50 fee applies. **

DOWNPIPE NOTICE: BY PURCHASING A MOTORSPORT/RACING PRODUCT ("PRODUCT"), YOU REPRESENT THAT YOU UNDERSTAND AND AGREE THAT: THE PRODUCT IS NOT DESIGNED TO MEET ANY APPLICABLE EMISSIONS STANDARDS, THE PRODUCT IS NOT C.A.R.B. COMPLIANT, AND IS NOT FOR SALE OR USE IN CALIFORNIA OR ANY JURISDICTION WHERE PROHIBITED BY LAW. BOOST DYNAMIC TUNING, LLC DISCLAIMS ANY CLAIMS OF EMISSIONS COMPLIANCE. BY PURCHASING, YOU AGREE IT IS YOUR RESPONSIBILITY TO INFORM YOURSELF OF ALL APPLICABLE LAWS.

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