RENNtech Intermediate ECU Upgrade | X166 | GL63 AMG | SUV | 638 HP / 695 LB-FT | M157 | 5.5L V8 BiTurbo | MY2013-15 bentley-bentayga-speed--2019-present--6-0l-twinturbo-w12-esr6746698 Fitment: ONLY for vehicles equipped

Fitment: ONLY for vehicles equipped with optional performance exhaust factory valves

These RENNtech rear diffuser extensions create an all new aggressive and functional aesthetic for the rear of the C190 - AMG GT R

This highly integrated prepreg carbon fiber spoiler compliments the sophisticated and refined CL exterior design language

FL and manufactured to highest specifications in USA

We have found the M276 engine stock performance numbers vary from the baseline figures claimed by Mercedes-Benz

RENNtech Intermediate ECU Upgrade | X166 | GL63 AMG | SUV | 638 HP / 695 LB-FT | M157 | 5.5L V8 BiTurbo | MY2013-15 bentley-bentayga-speed--2019-present--6-0l-twinturbo-w12-esr6746698 Fitment: ONLY for vehicles equippedIntermediate ECU Upgrade Up to 638HP 695LB FT Gains: +64HP & +72LB FT RENNtech M157 Biturbo ECU+ Upgrades are TV approved! Our proprietary ECU+ upgrade for the Mercedes M157 Biturbo 4 MATIC engine offers huge gains in performance across the entire RPM range without sacrificing around town comfort or daily driver reliability. Our intermediate level ECU upgrade offers huge gains in performance across the entire RPM range without sacrificing around town