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APR Stage 2 Downpipe Upgrade: Audi S6 4.0T

Dowmpipe Upgrade: 4.0T S6 Audi | Image 1

The Redline Speed Worx (RSW) Team is pleased to present the ultimate Cast Downpipe Upgrade for the Audi 4.0T found in S6, S7, S8, RS7, and A8! The APR Stage 2 Downpipe Exhaust System Upgrade replaces the restrictive factory catalyst cross pipes and resonators with an upgraded 76mm stainless steel mandrel-bent system, featuring port-matched cast inlets, high-flow catalysts and various other features.

Expect better throttle response, more horsepower and an intoxicating exhaust note, while remaining civilized during normal daily driving. The APR Stage 2 Upgrade is the best performance upgrade for the 4.0 TFSI following the APR Stage 2 ECU Upgrade and it’s all designed and assembled in-house, using premium materials and world-class manufacturing techniques few can match.

Dowmpipe Upgrade: 4.0T S6 Audi | Image 2Dowmpipe Upgrade: 4.0T S6 Audi | Image 3


  • More power and better response


    Expect a decrease in turbo lag with power and torque gains as high as 59 HP and 95 FT-LBS of torque over APR Stage I!
  • Full 76mm downpipe system


    The APR system is a full downpipe upgrade as it replaces the kinked 60mm catalyst cross pipes and resonated midpipes with straight through, 76mm mandrel-bent tubing.
  • Port-matched investment-cast downpipe inlets


    The factory inlets are restrictive. APR’s cast system allows for massive, port-matched inlets that smoothly neck down over a long distance. The result is improved flow, better response and more power.
  • Dual, high-flow catalysts


    GESI’s encapsulated catalysts are known for their strength and performance. Expect lower emissions, reduced noise and less exhaust smell compared to catless setups, all without negatively impacting performance to over 1,000 HP. Furthermore, with the catalyst moved, expect a cooler engine bay!
  • Compatible with the OEM catback exhaust


    Bolt-on and go! The system is fully compatible with the factory catback exhaust.
  • APR Stage II ECU Upgrade price waived


    With every APR downpipe purchase comes a free upgrade to Stage II from Stage I, saving consumers hundreds of dollars!
  • Limited lifetime warranty


    The best system on the market also carry the best warranty in the industry!

Dowmpipe Upgrade: 4.0T S6 Audi | Image 4

The cast inlets, piping and other components are made from the the high-nickel content, premium-grade stainless steel known as T304L. This material was chosen for its excellent corrosion resistance, strength and appearance. The castings are tumbled to smooth and de-burr any imperfections, and all piping is brushed clean before entering the CNC controlled mandrel benders. TIG welding is used at all connection points, and was chosen for its strength and appearance. Each weld is argon back purged during assembly to increase strength and consistency of the welds. The gusseted brackets are CNC laser cut and bent to provide strong mounting points to the factory mounting hardware.

APR Stage 2 Upgrade for Audi S6 | Image 5

Thats all well and good, but how much POWER does the APR Downpipe Upgrade make on my Audi S6 / S7?

The Audi S6 / S7 C7.5 on 93 Octane Fuel (Pump Gas) produces 518 HP & 639 TQ. This is an increase of +36HP & +58TQ over a current APR Stage 1 Upgrade.

Dowmpipe Upgrade: 4.0T S6 Audi | Image 6Dowmpipe Upgrade: 4.0T S6 Audi | Image 7

For the best results, APR recommends installing the APR Stage 2 ECU Upgrade. The upgrade price is waived for APR Stage I ECU Upgrade customers with purchase of the APR downpipe upgrade.

Dowmpipe Upgrade: 4.0T S6 Audi | Image 8

APR Stage 2 ECU Upgrade Pricing

  • Audi S6 / S7 (C7 / C7.5) – $374.99 or Free with Downpipe Purchase
  • Audi A8 / A8L (D4 / D4.5) – In Development
  • Audi S8 (D4 / D4.5) – $499.99 or Free with Downpipe Purchase
  • Audi RS7 (C7 / C7.5) – $749.99 or Free with Downpipe Purchase

APR Stage 2 Audi S6 | Image 9


  • Pricing: Please contact an APR Importer for pricing outside the USA.
  • Availability and ECU Compatibility: Stages, programs, and features may not be available for all ECUs.-
  • ECU Revision Notice: Multiple ECU revisions exist for each platform. APR software may be temporarily unavailable when factory updates are applied. An APR dealer can check availability in person, or over the phone if the ECU boxcode/revision is known.
  • Stage II Pricing: Customers who have purchased an APR ECU Upgrade before February 16th, 2015 are exempt from upgrade fees.

If you are interested in upgrading your 4.0T Audi S6, S7, A8, S8, or RS7 with APR’s Cast Downpipes and Stage 2 ECU Tuning Contact our Team Today to Schedule Your Appointment!


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