Renntech ECU upgrade SL550

Our proprietary ECU upgrade for the Mercedes M278 engine in the new SL 550 offers huge gains in performance across the entire RPM range without sacrificing around town comfort or daily driver reliability. Our ECU tune offers the biggest performance gains on the market translating to an astonishing 515 HP and 590 lb/ft at the crank! SL 550 (R231) Stock Performance: 429 HP @ 5,250 RPM; 516 LB-FT @ 1,800-3,500 rpm Note: Mercedes M278 engine performance when measured obtains higher numbers that rated from factory. Modified Performance: 515 HP @ 4900 RPM; 590 LB-FT @ 4100 RPM