You can find the chip tuning file for your Mercedes-Benz S W221 - 2005 - 2013 420 CDI 320hp vehicle on our site. These files are created especially for you and handed to you. All our Tuning files are extensively tested on Dynometer. The development of the tuning file for your Mercedes-Benz S W221 - 2005 - 2013 420 CDI 320hp vehicle is the result of a special product by EcuPrime Engineers. In addition, we can increase the power of your vehicle from 320 HP to 360 HP, 730 Torque to 820 Torque.