Armytrix Oct. Cat. 2022
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Weistec M278 ECU Tune W.2 Mercedes-Benz with Race Exhaust 2011-2020



Model #05-278-00060-8

Shopper Award

This product is for Racing Competition only and is not legal for use in highway or street vehicles or other non-racing competition off-road vehicles.

Purchasing this product requires you to sign our Vehicle Compliance Waiver here.

As an industry leader in tuning and calibration, Weistec Engineering is proud to introduce the much anticipated ECU tune for the bi-turbo M278 vehicle lineup. After months of painstaking dyno and road tuning, they are proud to introduce the most powerful ECU upgrade ever released for the M278 engine. Fully developed in house, Weistec ECU tune has surpassed the 540 horsepower mark on a completely stock vehicle with no other modifications.


  • Increased Horsepower and Torque
  • Eliminate top speed limiter
  • Increased throttle response
  • Optimized boost, fuel and spark
  • Credit towards M156 Supercharger Systems
  • Weistec Horsepower: 588 (Stock - 429)
  • Weistec Torque: 765 (Stock - 443)
  • Mercedes-Benz Base (W216) CL550 Twin Turbo 4.7L V8 (M278) 11-14
  • Mercedes-Benz Base (W212) CLS550 Twin Turbo 4.7L V8 (M278) 12-18
  • Mercedes-Benz Base (W212) E550 Twin Turbo 4.7L V8 (M278) 2012-2014
  • Mercedes-Benz Coupe (W212) E550 Twin Turbo 4.7L V8 (M278) 12-17
  • Mercedes-Benz Base (X166) GL450 Twin Turbo 4.7L V8 (M278) 13-14
  • Mercedes-Benz Base (X166) GL550 Twin Turbo 4.7L V8 (M278) 13-15
  • Mercedes-Benz Base (W166) GLE550 Twin Turbo 4.7L V8 (M278) 2016-2020
  • Mercedes-Benz Coupe (C292) GLE550 Coupe Twin Turbo 4.7L V8 (M278) 2016-2020
  • Mercedes-Benz Base (W166) ML550 Twin Turbo 4.7L V8 (M278) 12-15
  • Mercedes-Benz Base (W221) S550 Twin Turbo 4.7L V8 (M278) 11-13
  • Mercedes-Benz Base (W222) S550 Twin Turbo 4.7L V8 (M278) 2014-2017
  • Mercedes-Benz Coupe (C217) S550 Coupe Twin Turbo 4.7L V8 (M278) 2014-2017
  • Mercedes-Benz Base (R231) SL550 Twin Turbo 4.7L V8 (M278) 2013-2020

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Vehicle Engine Notes
Mercedes-Benz CL550

2012-2013, 2015-2017
Mercedes-Benz CLS550

Mercedes-Benz E550

Mercedes-Benz GL450

Mercedes-Benz GL550

Mercedes-Benz GLE550

Mercedes-Benz ML550

Mercedes-Benz S550

Mercedes-Benz SL550

What Is Weistec Engineering?

Based out of Orange County, California, Weistec Engineering is an industry leader in research, development, and design. While the company was only established in late 2010, founder Michael Weiss and his partner Steve Atneyel both have an impressive track record of working with some of the fastest and most powerful vehicles in the world. The duo were both engineers for major American OEM and aftermarket performance companies; Michael was involved with advanced engineering, while Steve specialized in computer calibration.

Michael Weiss and Steve Atneyel decided to branch out on their own and combine their expertise and experience. The pair were, and still remain, avid Mercedes enthusiast and realized that there was a huge gap in the market for a company dedicated to engineering state-of-the-art performance systems for cars powered by motors like the M156 and M159 AMG. Since its inception over a decade ago, Weistec has grown to provide customers with the highest level of satisfaction and value through unyielding tests and continuous improvements in Mercedes products and performance. 

What Does Weistec Offer?

Engineering and design are the two core services of Weistec Engineering. The Weistec team offers an array of services and capabilities thanks to the team’s combined experience from multiple fields. Whether you have a new idea or are looking to improve an existing design, Weistec can bring your concept to reality while protecting your vehicle’s design form and engineering function. Services include CAD, CAM, rapid prototyping, CNC machining, laser cutting and etching, casting, plastic injection molding, 3D laser scanning, and much more.

Weistec Engineering also offers a comprehensive line of products to the import and exotic market, covering vehicles such as Mercedes-Benz, Audi, Pagani, Alfa Romeo, BMW, McLaren, Ford, Aston Martin, and Maserati. No matter what type of upgrade you are looking for, Weistec has something for everyone when it comes to performance products, suspension parts, electrical components, interior/exterior accessories, and wheels/tires.

Weistec Engineering keeps nearly every aspect of its production process in house to guarantee only the highest quality. From conceptual 3D designs to in-house manufacturing and, ultimately, road and track testing, Weistec boasts relentless attention to detail on everything it offers. Specializing in computer-aided design and vehicle calibration, Weistec has the ability to manufacture quality products that are capable of withstanding even the most rigorous testing conditions. From OEM vehicle manufacturers to the aftermarket performance enthusiast, Weistec aims to deliver innovative solutions that address a wide range of client needs and desires. 

Find Weistec Parts at Vivid Racing

Vivid Racing carries an extensive lineup of Weistec products to suit all your needs and preferences. Our inventory is virtually endless with everything you could possibly need to upgrade your vehicle in terms of performance, power, handling, suspension, aesthetics, and accessories. If you cannot find what you are looking for above or need help choosing a product for your needs, please give us a call at (480) 966-3040. We will advise you on the possible options and walk you through the entire purchase process to ensure a hassle-free experience.

Weistec Limited Warranty

1. Warranty on Weistec Turbocharger Systems, Supercharger Systems, Exhaust Systems and Engine Accessories

12 month Weistec Limited Warranty. Valid 12 months from sales date with valid registration.The following exclusions apply to all Weistec Limited Warranties.

Weistec's limited warranties do not cover any of the following damages or items:
  • Damages to and/or failure of any non-Weistec component or equipment on a vehicle including, but not limited to, the engine, electrical system, transmission and differentials.
  • Damage caused by "Acts of God", normal wear and tear, or damage to a vehicle or engine caused by, tuning by others, collision and/or engine failure.
  • Any costs incurred for towing or downtime of the vehicle.
  • Any rental vehicle costs
  • Any labor costs to diagnose problems or to remove or replace the Weistec products; or any damage caused by the use of another company's product.
  • Any shipping costs.

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