Fit your 4.0 biturbo C63 S AMG  with the best dry air filters you you can get.  The AFE Pro DRY S air filters will increase power and reduce fuel consumption ( if you can keep your foot of the gas). These are Dry filters, so there is no messy oil needed that can cause problems with yoru engine. This is a great standalone mod for your 4.0L C63 S AMG or a highly modified one.