Mercedes-Benz 5.5L BiTurbo Alpha Series Downpipes

Now available! The Mercedes-Benz 5.5L BiTurbo Alpha Series Downpipes for your 2012-2013 or 2014+ E63/CLS63 AMG are the ultimate solution for improving power, throttle response and exhaust note without sacrificing quality, fitment or design.  If you are looking for the highest quality downpipes for your M157 engine look no further!

Alpha E63/CLS63 Catless Downpipes

Designed To Out Flow The Competition

Each Alpha BiTurbo Downpipe runs 3” (76mm) tubing for optimum flow all the way to your factory or aftermarket cat-back exhaust.  Our competitors chose to mimic the factory passenger side piping where it necks down at the connection creating turbulence and hurting exhaust flow and power.  This is a more cost effective way to make the system connect to the cat-back portion of the exhaust but it hurts flow by creating a bottle neck in the system.  This is not a compromise we were willing to make so our Engineering team implemented a ball-joint style connection retaining a full 3″ diameter maximizing your power gains.  On our test vehicle +30HP and +35ft-lbs were seen on the cat-less version!

Unparalleled Fitment Through Proper Engineering

These BiTurbo downpipes aren’t something we quickly whipped up in a fabrication shop.  These are properly designed and engineered using a CMM laser scanner for a perfect fit and space optimization.  By choosing a 3 piece design we’ve provided improved adjustability and fitment making them easy to install.  Placement of each O2 sensor bung was carefully chosen, eliminating the need to extend factory 02 sensor wiring. All brackets mount to their stock locations and each downpipe is routed in such a way that you DO NOT need to remove the factory heat shielding. All designed for a clean and proper OEM-like installation.  When you choose our Alpha Series Downpipes, there is no need to hack up your prized possession.

The Difference Is In The Details

Another unique benefit is our GESi racing catalytic converter option.  These 300 cell count units provide nearly no disruption in flow and feature a staked in design to hold the catalyst firmly in place.  Many competitors offer a low quality converter option to keep the cost low and profits high. Often these units fail due to poor construction and inferior materials.  When you choose Alpha you will remain emissions compliant and worry free for years to come.

Alpha E63/CLS63 Downpipes with GESI Catalytic Converters


Do it right the first time, order your BiTurbo Alpha Series Downpipes today!

Exclusive Benefits

  • Big increases in power throughout the entire power band
  • 3″ (76mm) piping all the way through to the cat-back connection
  • +30HP and +35ft-lbs gain over stock downpipes (non-catted)
  • +15HP and +15ft-lbs gain over stock (catted)
  • Improved turbo & throttle response
  • Eliminate turbo lag
  • Exotic exhaust note
  • 3 piece design for precise and proper fitment
  • Retains factory heat shielding
  • Premium race catalytic converters
  • Mates up to stock and aftermarket exhaust systems
  • Unrivaled fit and finish
  • Includes ALL necessary parts and hardware for installation


  • 100% low carbon 304 Stainless Steel construction
  • 3″ (76mm) piping with .065″ wall thickness
  • 300 cell race catalytic converter (optional)



  • Alpha Series Mercedes-Benz 5.5L BiTurbo Performance Exhaust System (2014+)



The goal of AMS is to provide the highest quality, best performing products available.
By utilizing research and development and rigorous testing programs AMS will never compromise the quality or performance of our products.

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On all orders over $199.99 in the lower 48.*Freight items not included*