Mercedes-AMG C63 S W205 M177.1 Modder's Guide

Mercedes-AMG C63/s Overview

Produced from 2015 to 2021, the Mercedes-AMG C63 S (W205) is powered by the legendary hand-built 4.0L twin-turbo M177.1 V8, paired with AMG's 9-speed (facelift) or 7-speed (pre-facelift) MCT transmission and rear-wheel drive. The W205 C63s features strong aftermarket performance potential; with only a tune and basic bolt-on modifications, the M177 can gain well over 150 crank horsepower while maintaining daily drivability.

C63 vs. C63 S and Facelift Differences

The C63 base, S, pre-facelift, and post-facelift models are largely the same, but have some  differences that are necessary to understand to extract the most performance possible.  The C63 S model includes a higher factory output (largely due to factory tuning), electronic limited-slip differential, dynamic engine mounts, stiffer suspension, and larger brakes.

The primary difference between the pre and post facelift models (omitting the redesigned styling and tech upgrades) relevant to performance modifications are the upgraded fuel pumps. These upgraded fuel pumps enable the post facelift C63/s to run higher ethanol concentrates, resulting in more power. Typically, pre facelift cars can run up to e20/e25 safely, and post facelift cars can run up to e35/e40 safely. Additionally, tuning post-facelift models requires a CPC tune to remove torque limitations.

If you're looking to run higher ethanol blends on a pre facelift car, it is recommended to purchase post-facelift high pressure fuel pumps from a C63s, or E63s fuel pumps if possible. For blends above e35/e40, we recommend Premier Tuning Group's HPFP upgrade.

Performance Modifications

Stage 1:

Consists of a quality ECU calibration, cold air intakes, and 91/93 pump fuel. With an aggressive custom tune, expect up to approximately 610 horsepower and 670 lb-ft of torque, reducing 60-130 mph times into the high seven-second range while maintaining factory-like drivability.

Stage 2:

Adds catless or high-flow downpipes alongside an ECU tune and cold air intakes. This setup typically produces up to 650 horsepower and 760 lb-ft of torque on 93 octane, with 60-130 mph times around the high 6-second range. A TCU and CPC (if post-facelift) tune is highly recommended to optimize shift speed and clutch pressure.

Stage 2+:

Introduces ethanol blends such as E30 together with optimized custom tuning. Depending on fuel quality and calibration, output can reach approximately 700 horsepower and 800 lb-ft of torque while lowering 60-130 times into the low six-second range. Upgraded spark plugs and improved cooling become increasingly important at this level.

Stage 3:

combines hybrid turbochargers with supporting hardware and custom tuning. Running E50 or E85 where supported, well-built setups can approach 850 horsepower and 930 lb-ft of torque with 60-130 mph times around five seconds.

Stage 3+:

represents the limit of the factory engine architecture. Large hybrid turbos, upgraded fueling, extensive cooling modifications, and custom calibration can produce well over 1,000 horsepower while achieving 60-130 mph times in the low four-second range. At this power level, transmission upgrades and additional drivetrain reinforcement become strongly recommended.

For custom tuning, we recommend working with our experienced Mercedes-AMG specialists such as A1 Automotive, MPE California, and Eurocharged. Please reach out to us via email (contact@gappedindustries) or Instagram (@gappedindustries) if you're interested in tuning your Mercedes-AMG,

Exterior Modifications

Front lips significantly improve the vehicle's appearance and can provide a modest increase in front-end stability at higher speeds. Side skirts visually lower the car and complement aggressive wheel fitment, while rear diffusers and rear spoilers (sedan, coupe) complete the rear profile. Mirror caps, steering wheels, and interior carbon are among the easiest upgrades for owners seeking an OEM+ look, and can be easily resold and fitted to other cars.

Wheel upgrades not only transform the appearance of the vehicle but also reduce unsprung weight when selecting forged options. Combined with high-performance tires, they provide one of the most noticeable improvements in both aesthetics and handling.

Suspension and Handling

While straight-line performance is the primary focus for many owners, lowering springs can dramatically improve the W205's stance and aesthetics. Quality coilovers can significantly improving both aesthetics and cornering ability if installed and cambered correctly, making them the better (though more expensive) option. A proper alignment following suspension modifications is essential for maximizing tire life and maintaining predictable handling.

Our Recommendations

For owners seeking an OEM+ build, we recommend coilovers, cold air intakes, subtle carbon fiber exterior components, and a Stage 1 ECU/TCU tune.

For a balanced street build, Stage 2 with catless downpipes, a TCU tune, additional carbon fiber aero, lighter forged wheels, and facelift/E63s fuel pumps (for pre facelift) provides the best combination of reliability and value.

For enthusiasts chasing maximum performance, a Stage 3 or Stage 3+ setup with hybrid turbochargers, upgraded HPFP and LPFP, ethanol tuning, enhanced cooling, and transmission upgrades unlocks the true potential of the M177 platform while maintaining surprising street manners when properly calibrated.

Interested in customizing your Mercedes-AMG or have an inquiry? Contact us via email (contact@gappedindustries.com) or Instagram (@gappedbyamg or @gappedindustries) for more information.