Mercedes CLS550 Bi-Turbo ECU Upgrade to Gain 80bhp VRTuned.com June 30, 2015 Product Info Standing straight down the strip looking at the front of the CLS550 and CLS63, only the well versed Benz enthusiast will know which is faster. The CLS550 comes with the 4.6-liter V8 that boasts twin...
