2021 - 2025 MILD HYBRID Audi 45 TFSI B9.5 A4 A5 2.0t ECU PERFORMANCE TUNE
Audi A4 / A5 45 TFSI B9.5 ECU Tune
Real Numbers. Real Pulls.
Tap a stage — power, fuel, and required mods at a glance. Wheel numbers with crank estimates; every stage's dyno session is on video below.
If your tuner doesn't show before & after dyno videos, you're being lied to.
A dynamometer is a before-and-after measuring tool — not an absolute output number. What can't be faked is the delta: same platform, same dyno, stock vs tuned — on camera, in the videos below.
How It Works — Remote Tune
No shop visit. We flash your A4 / A5 over the internet while you watch it happen live on your screen.
Schedule — after purchase, book your remote flash session with BDT.
Set Up — Windows laptop with TeamViewer, our OBDII cable in the port, battery maintainer on the car, key in accessory.
We Flash It — BDT remotes into the laptop and runs the whole flash while you watch live.
Drive — key off on command, unplug, done. A few fault codes right after flashing are normal; they clear after a short drive cycle.
This ECU family flashes via a live BDT remote session. Self-flashing with the BDT Flasher lands when this platform is ported.
What's Included
Watch The Proof
Every stage on the rollers, the JB4 comparison, and real customers. Sound on.
Dyno Session — Stage 1
Dyno Session — Stage 1+
Dyno Session — Stage 2
Dyno Session — Stage 2+ E85
BDT Stage 2 vs JB4 Stage 2
Crackle Pops — B9.5
Customer Reviews — Live Call
Customer Supplied Video
What Your Car Needs, Per Stage
If it is not listed as required, the tune runs without it.
| Part / Upgrade | S1 | S1+ | S1+ E85 | S2 | S2+ E85 |
|---|---|---|---|---|---|
| High-Flow Exhaust | — | — | — | REQ | REQ |
| Intercooler Highly recommended from Stage 1+ E85 up | REC | REC | REC | REC | REQ |
| Air Intake | REC | REC | REC | REC | REC |
| Drivetrain Inserts | — | — | REC | REC | REC |
TCU tune is not available on this platform. Final output varies with fuel quality, altitude, temperature, and vehicle health — BDT publishes live before/after runs for transparency.
Maintenance
| Maintenance Item | Interval |
|---|---|
| SPARK PLUGS NGK R7438-8 Racing Plugs | 15-20K mi |
| OIL CHANGE 5W-40 Liqui Moly • OEM FILTER ONLY | 5K mi |
| DSG / MANUAL TRANS FLUSH & FILTER OEM only | 30K mi |
| MAP SENSORS OEM only • intake / before throttle body | 80K mi |
| PCV ASSEMBLY | 80K mi |
| INJECTORS + CARBON CLEANING Do them on time to avoid misfires, lean conditions, and long-term damage | 85K mi |
Late Policy: If you schedule an in-person flash and arrive late without notice, a $50 fee applies. Reschedules must be made at least 1 hour prior.
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-adopting state.
Assumption of Risk and Waiver of Liability
By purchasing and/or installing this product, you agree to:
- Assume all risk and responsibility for compliance with applicable local, state, and federal laws and regulations.
- Waive all claims, liabilities, and legal actions against Boost Dynamic Tuning, LLC, its officers, directors, employees, and affiliates arising from the purchase, installation, or use of this product in violation of any applicable law.
- Release Boost Dynamic Tuning, LLC from any and all damages, injuries, or penalties resulting from improper or unlawful 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 inconsistent with this disclaimer, misrepresentation of vehicle use, or violation of any emissions laws or regulations.
Final Notice
This product is sold "as is" and "with all faults", with no warranties, expressed or implied, regarding legality for public highway use or emissions compliance. It is the sole responsibility of the end-user to determine legality 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.
HIGH-FLOW EXHAUST 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, WHETHER IN THE USA OR OTHERWISE, THE PRODUCT IS NOT DESIGNED TO BE C.A.R.B. COMPLIANT, AND THAT THE PRODUCT IS NOT FOR SALE OR USE IN CALIFORNIA, USA NOR ANY OTHER JURISDICTION WHERE THE SALE OR USE IS PROHIBITED BY LAW. BOOST DYNAMIC TUNING, LLC MAKES NO REPRESENTATIONS, WARRANTIES, OR CLAIMS THAT THIS PRODUCT COMPLIES WITH ANY APPLICABLE EMISSIONS LAWS AND EXPRESSLY DISCLAIMS ANY AND ALL SUCH REPRESENTATIONS, WARRANTIES, AND CLAIMS, WHETHER EXPRESS OR IMPLIED. BY PURCHASING THIS PRODUCT, YOU REPRESENT, WARRANT, AND AGREE THAT IT IS YOUR RESPONSIBILITY TO INFORM YOURSELF OF ANY LAWS OR REGULATIONS THAT MAY APPLY TO YOUR PURCHASE AND/OR USE OF THE PRODUCT.
Reviews
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Solid
Super nice, good power enhancement and burbles are nice, long duration on the crackles though, noticeable gas usage when spamming burbles
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From sleepy to sleeper
Stage 1+ on my 2022 A4 has changed every on-ramp, stoplight and tailgater. My kids are always asking for launch control. Mileage is improved when not tempted by the torque. This is now my Goldilocks car.
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Absolutely ridiculous first pull — the real deal
This is the real deal. Absolutely ridiculous first pull. No snake oil here. This dude knows his stuff. He takes the time to custom tune for your car. Not just a copy of someone else. He goes above and beyond to answer questions in detail and makes you comfortable with it. I'm excited for the future TCU tune. I will definitely be jumping on that. If you are looking for a safe, reliable, absolute beast of power you can feel. Get BDT.
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Drives like a whole new car
This thing drives like a whole new car. Great customer support from an expert that gives your vehicle the attention it deserves.
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Love the crackle pops — no complaints
Really improved driving characteristics. Love the deceleration crackle pops. Definitely a good tune. So far no complaints for reliability. Keep up on maintenance and you'll be all good.
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Immediately noticeable difference
Installed the Stage 1+ tune and the difference is immediately noticeable. Throttle response is much sharper, power delivery is smooth, and the car still feels reliable as a daily driver. No issues so far and very happy with the results.
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Power is insane — feels like OEM when you want it
The tune woke the car up I'm so happy with it it's so fast but when you want to drive chill it drives smooth feels like it's OEM it just drives so freaking fast now it's nice I'm happy I'm so happy the power is insane I feel like I could smoke a Mustang now it's hella good
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Night and day difference
Boost did an amazing job; great service. Love my car. Stage 1+ really picked it up. I'd recommend to anyone.
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Over 300 WHP daily — completely different car
Grabbed the Stage 1+ from BDT for my 2023 Audi A4 b9.5 and holy ****! The car feels like a completely different car, woke it right up and is a pleasure to drive. Im giddy walking to the parking lot after work because I get to daily drive over 300 whp. The launch throws you in your seat, and with an intake, it defiantly doesn't sound like a little 4 banger anymore. Cheers BDT team!