Hi, I own a 1999 Mercedes Benz C280 Sport Sedan. I was wondering what kind of upgrades were available and what kind of extra performance I could expect. Performance now isn't bad, but for what I would like it is a little shabby, topping out around 131. I was also wondering if anybody knew the speed the stock tires are rated for, I am not sure if my tires are just getting old or if the high speed driving has worn them down. Any suggestions or comments would be greatly appreciated!