You should check out the performance products from Kleeman if you're looking for a brand name Mercedes Benz tuner.
For your W202 C280, they do offer various performance upgrades for your engine. Options includes a supercharger, headers, (maybe camshafts), ECU re-program, exhaust, upgraded suspension/springs, etc.
Their website is:
- ONLY REGISTERED AND ACTIVATED USERS CAN SEE ALL LINKS - CLICK HERE TO REGISTER