Milltek 80mm Large Bore Downpipe & Hi-Flow Sports Cat - Audi RS6 C8 - SSXAU910

The Milltek 80mm Cat Back Large Bore Downpipe & Hi-Flow Sports Cat is a turbo-back component engineered for Audi RS6 C8, RS7 C8, and S8 D5 models (2019+). This system optimizes exhaust flow from the turbos to the catalytic converter, designed to pair with OE or Milltek cat-back exhausts.

Constructed from T304L stainless steel with a mandrel-bent 3.15" (80mm) bore and Milltek's high-flow 200 CPSI catalyst, this downpipe delivers measurable gains in boost response and mid-range torque. Direct fitment uses OEM hangers and mounting points—no modification required. Stage 2 ECU software is required for full optimization.

Fitment:

• Audi RS6 C8 4.0L V8 bi-turbo (2020+) — Performance Edition
• Audi RS7 C8 4.0L V8 bi-turbo (2019+)
• Audi S8 D5 4.0 TFSI V8 Sedan — Standard wheelbase (2020+)
• Audi S8 D5 4.0 TFSI V8 Sedan — Long wheelbase (2020+)

Fits OE Cat-Back.

Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.

Specifications

• Pipe diameter: 80mm (3.15")
• Fitting time: 4.5 to 5 hours, including removing the factory system
• Off-road / competition use only. Not legal for use on public roads in the US.

Fitment

• Audi > RS6 > C8 4.0 V8 bi-turbo in Performance Edition > 2020 and Later
• Audi > RS7 > C8 4.0 V8 bi-turbo > 2019 and Later
• Audi > S8 > D5 4.0 TFSI V8 Saloon/Sedan - Long Wheel Base (GPF US/ROW Models) > 2020 and Later
• Audi > S8 > D5 4.0 TFSI V8 Saloon/Sedan - Standard Wheel Base (GPF US/ROW Models) > 2020 and Later

• Free US shipping on orders over $250.
• Free pickup at our Dallas shop, usually ready within 24 hours.
• Unused parts can be returned within 30 days. Tunes, opened electronics, merch and installed parts are final sale.
• Want it installed? Book the install at thegbmotors.com.

Full details are on our shipping and returns page.