Don't take this the wrong way, but the best place to start is tightening up the nut behind the wheel.
Take a good driving school class if you can. Bondurant is excellent, as is the Skip Barber classes, and others. Learn about how cars behave when subjected to different inputs, and how things are different in different types of cars. Learn it in a practical environment, where you can go out and try it on a closed course. YOu will get significantly faster, and any suspension improvements you make after that will net a greater improvement, and it will help you to understand what things you want to try to do to improve suspension.
Also, a better driver will make any car faster.
