Renntech ECU upgrade SL63

Our proprietary ECU upgrade for the Mercedes M157 engine 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 with our dyno results increasing performance to an astonishing 669 HP and 734 lb/ft at the crank! This allows a CLS 63 to run the quarter mile on D.O.T. street tires in an impressive 11.3 seconds at 125 mph with 0-60 mph coming in a mere 3.4 seconds. Equipped with drag radials on the CLS we were able to achieve an even more impressive quarter mile time. The CLS was able to rocket down the drag strip; clocking a quarter mile time of 10.9 seconds @ 129 mph with 0-60 mph coming in 3.2 seconds! Note: We have found the new M157 engine stock performance numbers vary from the baseline figures claimed by Mercedes Benz. We typically see slightly higher baseline numbers than claimed by the factory. SL 63 (R231) Stock Performance (Without Performance Package): 530 HP @ 5250 RPM; 590 LB-FT @ 6000 RPM Modified Performance (Without Performance Package): 669 HP @ 5500 RPM; 734 LB-FT @ 3800 RPM SL 63 (R231) Stock Performance (With Performance Package): 557 HP @ 5500 RPM; 664 LB-FT @ 6000 RPM Modified Performance (With Performance Package): 669 HP @ 5500 RPM; 734 LB-FT @ 3800 RPM