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M178 ECU Tune
Purchase M178 ECU Tune
  • SKU: 05-178-00041-6

    M178 ECU Tune

  • Advertised gains are estimates of HP and Torque “at the engine” calculated from gains as measured on a Dynojet Dynamometer in ideal conditions and typically show the largest possible change.  Actual gains are dependent on the following: Learn More about Crank HP Vs Wheel HP

    Model – Manufacturers use the same engine in multiple model vehicles and often times they are in a different state of tune, for example: 2008 C63 and a 2008 CLK Black Series.  Both have the same engine, but the C63 has 451hp while the CLK63 has 500hp.  Naturally the C63 will show more gains as it starts at a lower level.

    Model Year – Similar to above, as time progresses, Manufacturers tend to slightly increase power output via software from one year to the next or offer “Performance Packages” with increased power.  The engines remain largely unaltered and as a result, final tuned output remains the same, while the gains are lower as the starting point is now higher.

    Fuel – Fuel quality is HIGHLY important with performance vehicles.  Low quality and/or low octane fuel will greatly impact engine output and potentially even engine health.  Top tier brand premium fuels should always be used to achieve the best results possible.

    Drivetrain – All wheel drive has higher drivetrain losses than rear wheel drive.  This results in lower numbers when testing on a chassis dyno.  Wheel/tire size and weight will also impact chassis dyno results

    Weather/Conditions – Temperature, humidity, altitude, and air density all impact engine performance.  Heat, high humidity, and thin air will all work towards reducing engine output

    Engine Health – Higher miles tends to result in increased build up and lower compression which can and will impact engine output.  Properly maintained engines will have better performance than abused or neglected engines.

    Supporting modifications – The highest power levels require supporting modifications.  Depending on the engine, this could mean forged internals, built transmission, upgraded fuel system, 110+ octane race fuel, etc.

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  • Prop 65 warning

    This product can expose you to chemicals including carbon black, silica - crystalline, formaldehyde, and lead which are known to the State of California to cause cancer, and lead, which is known to the State of California to cause birth defects or other reproductive harm. For more information go to

Weistec Horsepower 605
Weistec Torque 624
Manufacturer Weistec
Street legal in all the US States No
Engine Family M178
Stock Horsepower 456
See more
year make model trim engine
2020 Mercedes-Benz AMG GT S Coupe (C190) Twin Turbo 4L V8 (M178)
2019 Mercedes-Benz AMG GT S Coupe (C190) Twin Turbo 4L V8 (M178)
2018 Mercedes-Benz AMG GT S Coupe (C190) Twin Turbo 4L V8 (M178)
2017 Mercedes-Benz AMG GT S Coupe (C190) Twin Turbo 4L V8 (M178)
2016 Mercedes-Benz AMG GT S Coupe (C190) Twin Turbo 4L V8 (M178)
2015 Mercedes-Benz AMG GT S Coupe (C190) Twin Turbo 4L V8 (M178)
See more

Product Description

All 2020 models require bench flashing at this time.

ECU Tuning Process: How do I get my ECU tuned?

+ 118 Wheel Horse Power + 134 Wheel Torque Peak Gains

The hand built M178 V8 Biturbo engine from AMG is a powerful motor from the factory proving it is very capable on and off the track, but even a perfect machine can benefit from finer tuning.  Using the latest calibration technology and countless hours of testing, Weistec was able to achieve massive gains in both horsepower and torque through out the powerband.  The Weistec M178 ECU Upgrade provides 118 wheel horse power and 134 wheel torque at lower RPMs along with substantial gains in the mid and high range, making the power delivery far superior from the factory calibration. 

Weistec AMG GT S ECU | Downpipe and Midpipe Power

[ Worlds Fastest ] Weistec AMG GT-S Quarter Mile


What does all this mean to you?  More power, sharper throttle response, and a complete focus on the driver makes this the perfect addition to your AMG for a much more enjoyable experience for you. 

Key Features:

  • +118 Wheel Horsepower Peak Gains*

  • +134 Wheel Torque Peak Gains*

  • Eliminated Top Speed Limiter

  • Improved Throttle Response

  • Optomized Fuel, Spark, and Boost

*Power gains vary based on model, modifications, fuel, and running conditions.

ECU Tuning Process: How do I get my ECU tuned?

Tuning Process: Cypher Handheld Tuner