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Stage 2 Billet Turbo Upgrade for Mercedes-AMG GT / GT S / GT C / GT R (R190) – M178 4.0L BiTurbo
Stage 2 Billet Turbo Upgrade for Mercedes-AMG GT / GT S / GT C / GT R (R190) – M178 4.0L BiTurbo
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Stage 2 Billet Turbo Upgrade — Mercedes-AMG GT (R190)
The Stage 2 Billet Turbo Upgrade is the largest factory-housing turbo upgrade available for the M178 4.0L V8 BiTurbo — engineered for serious power while keeping true bolt-on fitment in the AMG GT.
Built for high-boost street cars, track builds and setups planning for more power later, the Stage 2 turbo dramatically increases airflow through custom billet internals while retaining OEM-style installation.
Vehicle Fitment
- Mercedes-AMG GT (R190) — M178 4.0L V8 BiTurbo
- Mercedes-AMG GT S (R190) — M178 4.0L V8 BiTurbo
- Mercedes-AMG GT C (R190) — M178 4.0L V8 BiTurbo
- Mercedes-AMG GT R (R190) — M178 4.0L V8 BiTurbo
Not sure your car is covered? Send us your VIN and we will confirm before you order.
What Makes the Stage 2 Turbo Different
Built around the largest turbo configuration that still fits inside the factory housing footprint — massive airflow capability without the complexity or fitment problems of a full custom turbo system.
- Largest factory-housing turbo available for the platform
- Billet compressor wheel — 55mm inducer / 73mm exducer
- High-flow turbine wheel — 55mm
- Fully bolt-on installation
Technical Specifications
Stage 2: compressor 55mm inducer / 73mm exducer · turbine 55mm
Factory turbo, for reference: compressor 41.7mm inducer / 56mm exducer · turbine 44.5mm / 50mm · A/R 0.57
The size difference shows how much additional airflow capacity this upgrade provides over stock.
What These Turbos Need
The turbo will physically install on a stock car. It will not make its numbers on one.
- Exhaust: catless downpipes
- Cooling: CSF 8187 auxiliary radiators, Wagner intercooler kit
- Intake: cold air intake kit, BMC panel filters
- Boost control: GFB DV+, VTA / BOV adapters
Core Return & Wastegate Instructions
- Core return required
- Remove your factory wastegate actuators before shipping your cores
- If turbos are received with wastegates installed, do not use them — reuse your original factory wastegates for known calibration and reliability
Who This Turbo Is For
- Owners targeting 850–1000+ HP
- Track-focused or high-boost street builds
- Future-proof setups planning for more power later
Need help confirming fitment or supporting mods? Contact us before ordering and we will help you build the setup correctly the first time.
