Performance tips needed

Hi, I am looking for performance tips that could gain power on low and mid range.
I have a 93 300E. It is a I6 engine, produce about 217hp and 233 torque.
I think my car is pretty slow,( is okay on the freeway) because of its weight. Even cars like GTI and integra GSR could beat me by spending like a couple hundred dollars ( on some kind of computer chip).
Also, I have put koni and H&R suspensions installed for handling improvement, but it just seem to work as I expected. Someone told me sway bars would help, because they are more important ??. Anybody knows what kind of sway bars are good. I notice that AMG makes the front sway bar for me , and I don't know if they are any good ?
Thank you for your time.
Pete 93 300E.