C300/C400/C450/C43/C63/E63 JB4 Direct Boost Control Add OnThis add on JB4 module provides direct control of your wastegate solenoid allowing the JB4 to hit higher boost targets in tuning situations where appropriate. The amount of offset applied is fully user adjustable in the JB4 interface using the "duty bias" and "FF" fields and automatically scales based on boost target. Applications C Class 2015+ C300 C400 C450 C43 2015+ C63 C63s AMGE Class 2017+ E63 E63s AMG