ECU Upgrade M157 5.5L V8 BiTurbo

The Renntech ECU Upgrade is an intermediate-level performance tune engineered specifically for the Mercedes-Benz M157 5.5L V8 BiTurbo engine found in C218 CLS 63 S AMG 4MATIC models from 2015-2018. This software-based enhancement delivers significant gains in horsepower and torque throughout the entire RPM range without compromising daily driving comfort or long-term reliability. The system is TÜV approved and is an ideal choice for drivers seeking increased power output while minimizing additional strain on driveline components. It also serves as a specialized solution for vehicles operating in regions with extreme temperatures, high altitudes, or limited fuel quality. Mandatory operational requirements include the use of 91+ octane gasoline. States or regions identified as having poor fuel quality may require a lower-power configuration; customers in these areas are encouraged to contact support directly regarding specialized tuning or race fuel options. Power figures are based on internal measurements of stock performance, with crank horsepower and torque calculations factoring in a 17% drivetrain loss for 4MATIC models.