W205 C63 & C63 S Turbo Upgrade Guide (M177)

The W205 C63 / C63 S with the M177 4.0L BiTurbo platform responds extremely well to tuning and bolt-ons, but once you’re pushing past the limits of the factory turbos, airflow becomes the bottleneck. This guide explains when turbo upgrades make sense, what power levels to expect, and how to choose the right turbo setup based on your goals.

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When Do You Need Turbo Upgrades on the M177?

With proper supporting mods and tuning, most Stage 2 W205 C63 / C63 S setups land around ~590 WHP / ~620 WTQ. Beyond this point, the factory turbos struggle to maintain airflow efficiently at higher boost levels.

If your goals include:

• More top-end power
• Stronger pull past mid-range RPM
• Additional headroom for aggressive tuning

A turbo upgrade becomes the natural next step once you’ve reached the limits of the factory units. If you’re still working through the basics, it’s worth stepping back to the complete W205 C63 / C63 S M177 performance guide to make sure airflow, cooling, and tuning are fully optimized before moving to bigger turbos.

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Turbo Option #1 – Stage 1 Turbo Upgrade (M177)

The Stage 1 Turbo Upgrade is the most popular choice for W205 C63 / C63 S owners who want a major power increase without sacrificing drivability. This setup retains OEM-style housings for perfect drop-in fitment while significantly improving airflow and boost efficiency.

Key Features

• Custom billet compressor wheel for increased strength and airflow
• Clipped exhaust wheels to optimize exhaust flow
• CNC machined components for precision and durability
• High-speed VSR balanced for smooth high-RPM operation
• OEM-style housings for true bolt-on installation

Boost response and drivability remain very close to stock thanks to OEM-style housings and properly balanced rotating assemblies.

Real-World Dyno Results (Stage 1 Turbo Upgrade)

Below is a real-world before-and-after dyno comparison on the same M177 platform. This illustrates exactly why turbo upgrades make sense once Stage 2 airflow and cooling are in place.

• Before Turbo Upgrade: 548.6 WHP / 751.4 WTQ
• After Stage 1 Turbo Upgrade: 653.8 WHP / 814.3 WTQ

The result isn’t just peak power — it’s a broader, stronger powerband with improved top-end pull. Torque carries further into the RPM range, and horsepower no longer falls off early like the factory turbos.

This is why the Stage 1 turbo upgrade is ideal for aggressive street builds that want real performance gains without sacrificing response or drivability.

This turbo is ideal for aggressive builds targeting 650+ WHP & 800+ WTQ while maintaining stock-like response.

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Turbo Option #2 – 1000 Stage 2 Billet Turbo Upgrade (M177 / M178)

The 1000 Stage 2 Billet Turbo Upgrade is the largest factory-housing turbo currently available for the M177 / M178 platform. This upgrade is designed for owners chasing maximum power potential while retaining bolt-on installation.

Key Features

• Largest factory-housing turbo available for M177 / M178
• Billet compressor wheel (55mm inducer / 73mm exducer)
• High-flow 55mm turbine wheel
• Fully bolt-on installation
• Proven high-power performance

Proven Results

A W205 C63 S customer achieved:

• 910 RWHP
• 880 RWTQ

Technical Comparison

Stage 2 Turbo:

• Compressor: 55mm inducer / 73mm exducer
• Turbine: 55mm

Factory Turbo (Reference):

• Compressor: 41.7mm inducer / 56mm exducer
• Turbine: 44.5mm / 50mm
• A/R: 0.57

Supporting Mods Required

• Downpipes
• Front + auxiliary heat exchangers
• Methanol injection or upgraded fueling
• High-flow intake setup
• Custom ECU calibration

This turbo upgrade is best suited for track-style builds, high-boost street cars, and owners targeting 850–1000+ HP.

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Important Installation & Core Notes

• Core return required
• Remove wastegate actuators before shipping your cores
• If turbos are received with wastegates installed, do not use them
• Reuse your factory wastegates for known calibration and reliability

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Which Turbo Is Right for You?

• Street-driven / aggressive builds: Stage 1 Turbo Upgrade
• Maximum power / future-proof builds: 1000 Stage 2 Billet Turbo

If you want a brutally fast but refined W205 C63 / C63 S, the Stage 1 turbo hits the sweet spot for most owners.

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Final Thoughts

Turbo upgrades unlock the next level of performance on the M177 platform — but only when matched with the right supporting mods and tuning. Choose the turbo that fits your goals, build around heat control and airflow, and the results speak for themselves.

Need help choosing the right turbo setup? Tell us your goals and supporting mods and we’ll point you in the right direction.