Now that I have achieved Red/White or Instructor status, should I modify my car to make it go faster?
Yes, with a recommendation. Do not change more than one thing at a time prior testing it out on the track.
Why do I not want to make more than one performance modification at a time?
If you are now going slower than you were before the 2 or 3 modifications, you will have a hard time figuring out which modifications caused the problem. Was it the suspension change, or the different tires, or maybe just the tire pressures?