RENNtech Stage I Turbo Upgrade Package | W463 | G63 AMG | 818 HP / 820 LB-FT | 4.0L V8 BiTurbo | M177 | MY2019+Includes Upgraded Turbos, ECU Upgrade, BOV Adapters, Air Filters and Fuel System Upgrade. Gains: Up to +176 HP +100 LB FT The Mercedes X463 G 63 AMG comes with the newest engine fully developed by AMG, the companys Affalterbach based performance division and long fabled engine builder. The result is nothing short of spectacular and the 4. 0L V8 BiTurbo engine is an incredible platform to build performance upon. In addition to that, the all new X463 G