since no one else seems to have pointed it out.
your car is 13 years old now and its highly doubtful you or any previous owners have maintained nor done any suspension upgrades, it's also highly doubtful you have the brakes or tires to handle high speeds and the braking associated with them. not to mention your experience level judging from your post and no formal training. you and your car are nothing but another statistic waiting to happen.
By the way, spend the 400 bucks, you only gain about 10 or so mph before aerodynamics kick in. Your in a focus, your not speed racer so learn to live with it.