The S58 engine in the G80 and G81 M3 is renowned for its forged factory strength, but pushing for 800+ horsepower or fitting larger hybrid turbochargers requires a reinforced engine architecture. Extreme cylinder pressures from aggressive ECU remapping test the limits of internal components under sustained high boost. Fortify your block using high-strength Forged Pistons and heavy-duty Forged Connecting Rods/Conrods. Secure your rotating assembly with high-tensile Upgraded Engine Bolts (ARP) and minimize internal drag using race-specification Performance Bearings (Conrod & Mains). Ensure a complete seal under elevated boost using heavy-duty Engine Gaskets, and optimize cylinder head airflow with Performance Camshafts and Valve Spring Upgrades.