C63 W205 RSS

Why Stage 3 Is the Real Power Threshold on the M177 The Mercedes-AMG C63 W205 runs the M177 4.0-liter twin-turbo V8, and in factory form it delivers between 469 HP (C63) and 503 HP (C63 S). Stage 1 and Stage 2 ECU tunes push that number to roughly 550-700 HP by optimizing boost maps, fueling, and ignition timing. But once you want 800 HP or more, the factory turbos become the bottleneck. They simply cannot flow enough air. A Stage 3 turbo upgrade replaces the factory IHI turbochargers with larger, purpose-built units featuring billet compressor wheels, Inconel turbine wheels, and...