Motorsport and driving in general is a dangerous thing. As much as everyone has a freedom to do whatever one pleases to do, one also needs to realize that freedom comes with responsibility. So be responsible to whatever you do and don't sue me.
Handling of a vehicle is determined by many variables. Some of these are tires, center of mass (a.k.a. center of gravity), chassis torsional stiffness, suspension geometry, suspension components (springs, shocks, anti-roll bars), etc.
There are many things that most people do not wish to change due to various reasons. For example, most people do not want to strip the interior of the car to lower the center of mass. It is understandable as it would make a very impractical street car. Installing roll cage is not a really good idea for a street car, either. Changing the suspension geometry is not recommended without thorough understanding of the vehicle dynamics. Changing suspension components is the easiest way to alter the handling characteristics of the vehicle.
Tires are black rubber things that provides the only contact with the
road surface. Friction between tires and the road surface creates
acceleration, braking (deceleration), and cornering. Most of you
learned in high school physics that:
Tire's frictional property can not be expressed as an equation really well. If I use the above equation, Cf will decrease with increase in Fn. As normal force increases, coefficient of friction decreases. As a results, friction force does not increase as much as increase in normal force.
Weight transfer is a shifting of loading on tires due to acceleration.
Increasing speed, braking, and cornering cause weight transfer. For
transverse acceleration, weight transfer can be expressed as:
This equation calculates the total weight transfer but does not calculate how much weight is transferred by front or rear wheels. It required more complicated equation and a lot more details and assumptions to calculate the weight transfer by each wheel, and I am not about to get into that.
Just remember that, if you make on end of the car stiffer, there will be more weight transfer at that end and lose some traction capability due to increase loading on that end.
Springs are energy storing device. They store energy by deflection.
Most springs are constant rate springs, i.e., amount of the force that
is stored is proportional to the deflection of the spring. It is
usually expressed as:
There are also progressive springs. Progressive spring's spring constant (k) increases with deflection.
OK, enough about what springs are. We can now talk what springs do in a car. Springs absorb bumps, limits the motion of the vehicle due to acceleration, braking, cornering, etc.
Shock absorbers dampen the motion of suspension. Shock absorbers do not absorb impacts; springs do. Shock absorbers are dampers.
Shock absorbers also control the transient motion of the vehicle. Shock absorbers control HOW the car nose dive when brake is applied. Springs control HOW MUCH car nose dives. Shock absorber controls HOW the car goes into roll when the steering is applied. Springs and anti-roll bar control HOW MUCH car rolls.
There are some adjustable shocks available. Adjusting the extension of the shock is called "rebound," and adjusting other direction is "bump."
Anti-roll bars are also known as roll bars, sway bars, anti-sway bars, etc. Anti-roll bars connect right and left wheel. They resist roll by twisting themselves, acting as torsion springs.
You have to understand few terms before I can explain how to tune suspension.
As you can see, changing one thing can alter the all three stages of the handling. You will have to make a compromise that best suits to your requirement. There are also more variables such as ride height of the vehicle, wheel alignment, tires, driving style, corss weight, etc., that can alter the handling of a vehicle.
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