from my experience with the 300E and the 300ce, don't do too much to the motor and for your car if you fell you must get wheels, do not go larger than 17" trust me, I have 18's and the tires are very very skinny and not the best for daily driving, great for high speed highway romps, the best idea would be to find some used 17" stock rims from another MB that someone is selling because they got aftermarket rims, this is a good idea because: 1. the bolt pattern should be similar, 2. less expensive than brand new wheels 3. if your not going to sink money into the car, this is a cheaper upgrade, I was very tempted to do a very very mild body kit, but my car rests too low as it is, I am not going to want to have to keep patching fiber glass. There are a few kits for your car, but I personally would save the money for keeping the car in top condition and running a good clean audio system. I swear by Bilstien shocks, and they will make a big difference over stock for ride and handling. Just trying to give some ideas.