You can get the c30 amg injectors, use a bigger map sensor from another later om651 engine, use the 320cdi om613 turbo, I've had mine hybrid too. Bigger exhaust, and better intercooling
Also fuel pump from a v8 400cdi and supporting mods are needed to fit the pump. Also better rail pressure sensor, all of the mods with need the map modified to allow them to work,