WU5K

I have the following mods on my car:
GFB blow off Valve
JB4 Tune
BMS pedal tuner
BMS cold air intake
Soon to install catless downpipe when it's nice outside.

I went for a drive and decided to give it a pull and at High RPM's I get a drastic boost drop and a low boost code. I've cleared the code when the car was off and it's not come back, I have not really put much load on the car since. I was looking into the code and am suspecting maybe the stock wastegate could not keep up to the increased boost. This is my first MB and am having trouble finding what specs my stock wastegate is and want to buy an upgraded one but do not know what to purchase because I do not know the specs.

Any suggestions and or help would be greatly appreciated. If maybe someone else has modded up their C300 and would have a better suggestion on what to upgrade to prevent the boost drop or if anyone can recommend the best aftermarket wastegate for the car I would appreciate that as well, also if there is some mod that I should look into doing that would be beneficial please lmk(I'm thinking about upgrading the intercooler soon too).

Thanks