CTS K04-X Turbo kit, Audi B7 / B8 A4 A5 Q5 2.0TFSI EA113

CTS Turbo’s K04-X turbo kit is a highly capable hybrid solution at a reasonable price. Designed specifically for B7, B8, and B8.5 generation Audi A4, A5, Allroad, and Q5 2.0T models, making it a popular choice, for example, as a tuning turbo for the Audi A4 B7!

The selection of smart upgrade turbos for longitudinal engines is surprisingly limited. While models like the Golf MK6R, Audi S3 8P, and similar cars have a wide variety of turbo options, the situation is not as favorable for longitudinal engine setups.

This kit includes a complete, ready-to-use hybrid turbo. The foundation is the CTS-spec HYBRID K04 CHRA, paired with a larger billet compressor wheel and a clipped K04 turbine wheel, all housed in CTS’s custom-designed compressor cover and turbine housing. Unlike hybrids that force large CHRAs into small factory housings, CTS’s solution is purpose-built to maximize airflow and durability, providing reasonable turbo lag and excellent power delivery.

The high-quality castings are CNC-machined and replace your factory turbo without requiring additional parts beyond supporting modifications. This setup is engineered to deliver optimal performance and reliability with supporting mods.

What’s the output?

With proper HYBRID K04-specific ECU tuning and supporting modifications, this turbo can deliver up to 400 HP. Remember that this turbo requires professional tuning to work optimally, and the fuel system, intake, intercooler, and exhaust must also be appropriately configured for the power levels. You’ll find solutions for all of these from us!

CTS K04-X EA113 Longitudinal at a glance:

• CTS-spec HYBRID K04 CHRA with heavy-duty thrust bearings
• 48.5/61 mm billet compressor wheel in 6+6 configuration (MFS – machined from solid)
• Clipped K04 turbine wheel
• K04-X specific compressor and turbine housings – not a reworked factory housing!
• OEM+ manufacturing tolerances for precise fit and durability
• VSR high-speed balanced for ultimate reliability
• Direct replacement for the factory turbo, no additional parts needed (aside from supporting mods)
• Includes OEM installation kit (gaskets and hardware)
• Note: Requires proper HYBRID K04-specific tuning for the ECU.

Compatibility:

• Audi A4 (2006–2009)
• Audi A4 (2009–2016)
• Audi A5 (2009–2016)
• Audi AllRoad (2009–2016)
• Audi Q5 (2009–2017)
• ROW vehicles: Please confirm fitment with your CTS Turbo dealer.

Our Recommendations:

• A better-flowing downpipe with a high-flow catalytic converter or decat is a must-have to ensure the turbo works correctly.
• Upgraded intake and intercooler systems
• For the B7 A4 model, a better HPFP (high-pressure fuel pump) and larger direct-injection injectors are needed depending on the power target.
• In some models, minor trimming of the factory coolant line bracket may be necessary.

Additional Information:
Check here: Turbo Installation Guide from the Manufacturer