In the end, every modification and adjustment for "handling" comes down to getting the maximum work out of those four little patches of where the rubber meets the road.
Race car handling is a very broad and very technical subject, and we're not going to pretend to cover this subject completely. With this site's main audience being the weekend racer using a predominantly stock car, we're going to focus on the basics of the physics involved, and the practical application of after market hardware.
If you're interested in an in-depth study of the physics and engineering behind leading edge handling, there are several excellent books about this topic, and you'll need those references.
Whether you're just beginning, or already have some race driving experience, you'll need to have a basic understanding of the physics involved in race car dynamics to maximize your performance. While you can go to any number of shops and buy hardware, you need to understand the purpose of each of the major components affecting the handling of the car, and how each of them affect each other. There is no point in blindly spending hundreds or thousands of dollars on fancy parts without knowing exactly what it is you're trying to accomplish, or how to adjust them for maximum performance. Having an understanding of handling physics, your car, and your goals, will help you know whether that killer part described in a magazine article or ad is going to help, or whether it needs something else at the same time to be effective.
If you've spent a lot of money on parts for your car and think it's not handling as well as it should be, it could be your driving, but it could also be a mismatch of parts because you (or your shop!?) didn't understand what the parts actually do and how they affect the whole car. Fine tuning a car's handling is about compromises. There is no single setup that will provide peak performance on all tracks, or even on all parts of a single track. To adjust for this, you will have to understand the forces and dynamics the car experiences during racing and how after-market handling hardware affects them.
Start with the basics we present here. With an understanding of what affects your vehicle's handling, you can decide on an upgrade path that suits your budget, and meets the needs of the skills you're developing.
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