CTS BOSS800 Turbocharger for Audi B9 S4/S5/SQ5
CTS BOSS800 Turbocharger for Audi B9 S4/S5/SQ5
TR-2251
- Fully secure checkout
- Trusted
- Rated and reviewed
Customer Reviews
Question about this product?
We're happy to help.
Shop safely
Secure your shopping experience with various safe and trusted payment methods.
Software Requirements
Software Requirements
Description
We are excited to announce our new BOSS800 hybrid turbo for the Audi/Porsche EA839 3.0T platform. This is a direct replacement upgrade that significantly increases airflow while retaining OEM-style fitment and drivability. This hybrid unit is optimized for higher boost efficiency and improved top-end power without sacrificing low-RPM response. The turbo utilizes an upgraded compressor and turbine configuration, allowing it to support a wide range of fuel blends from pump gas to ethanol mixes. All testing shown was performed on the same vehicle and hardware, with only fuel content changed between runs.
Power gains scale predictably with ethanol content, showing strong midrange torque and sustained power through the upper RPM range. Boost response remains smooth and controlled, making the turbo suitable for both street and track-focused builds. This turbo pulls all the way to redline and has more potential with additional fueling.
The best part is that this is a full brand-new unit that does not require a core and it is compatible with many off-the-shelf stage 3 tuning.
Turbocharger specs:
- 66mm turbo inlet, larger turbo inlet is required
- 66mm 7+7 design billet compressor wheel
- 63mm 9 blade high-flow turbine wheel
- Stainless steel exhaust housing, matched to increased flow of the turbine wheel
- Heavy duty bearings and thrust washers
- VSR balanced
- Compatible with any exhaust, any charge pipe, and 66mm turbo inlet
- Transfer of factory diverter valve and boost pressure relief valve (06M133554A, pay attention on how it is installed).
Dyno Results from our friends at Logic Street Performance (1/4 mile time: 10.29 at 140mph)
-
Run 1 – 92 Octane:
561 hp / ~532 lb-ft -
Run 2 – E50 (92 + pump E):
640 hp / ~643 lb-ft -
Run 3 – E55 (92 + pump E):
658 hp / ~654 lb-ft -
Run 4 – E60 (92 + pump E):
671 hp / ~663 lb-ft
**Note that these results were achieved in a vehicle with full bolt-ons and upgraded fueling system (RS6 injectors, HPFP and LPFP upgrade, 4BAR Map sensors) and Logic Street Performance stage 3 tuning. Your result may vary.
Parts required for installation (not included):
- 2x 06M253039G – exhaust manifold gasket
-
1x 059253232C – exhaust ring gasket
-
1x WHT006901A – oil feed o-ring
-
3x WHT007689 – oil feed and coolant o-ring
-
4x WHT004982 – barrel nut
- 4x N91130801 – exhaust nut
-
1x WHT007923 – connecting pipe o-ring
-
2x 8K0253115K – exhaust gasket
- 1x N0138441 – seal for boost pressure relief (jet) valve
- 2018 – 2023 B9/B9.5 Audi S4 3.0T
- 2018 – 2023 B9/B9.5 Audi S5 3.0T
- 2018 – 2023 B9/B9.5 Audi SQ5 3.0T
- 2020 – 2022 4M Audi Q7 3.0T
- 2019 – 2022 4M Audi Q8 3.0T
- 2019 – 2022 C8 Audi A6 3.0T
- 2019 – 2022 C8 Audi A7 3.0T
- 2020 – 2024 C8 Audi AllRoad 3.0T
- 2019 – 2023 D5 Audi A8 3.0T
- 2019 – 2021 Porsche Macan S 3.0T
- 2019 – 2023 Porsche Cayenne 3.0T

Shopping Safely
At our Shopify store, we prioritize your safety and security. Here's how we ensure a secure shopping experience:
1. Secure Transactions: We use advanced encryption to protect your personal and payment information, ensuring it is safely transmitted and safeguarded.
2. Trusted Payment Gateways: Our store integrates with trusted payment gateways, ensuring your transactions are processed securely and efficiently.
3. Data Privacy: Your privacy is our top priority. We follow strict data protection policies to keep your personal information confidential and secure.
4. Secure Platform: Shopify provides robust security features and continuous monitoring against vulnerabilities, ensuring a safe shopping environment.
5. Verified Merchants: We are a verified merchant on Shopify, committed to providing authentic and high-quality products.
6. Transparent Policies: Our clear return, refund, and shipping policies provide peace of mind, knowing we stand behind our products.
7. Customer Support: Our dedicated customer support team is ready to assist with any concerns or questions you may have.
Shop confidently at our Shopify store, where your safety and satisfaction are our top priorities.
$2,249.99