1. Introduction
anti-roll bar For many people, anti-roll bar is just a humble hardcore child, but you may not know this child will be your hardcore a significant impact on the car, but you never really understand its function, and now we have to explore the secrets in this chassis. Anti-Roll Bar is usually translated into anti-roll bars, to popular thing you can call it “under the rod.”
two modified anti-roll bars front and rear, although more than million to spend on your budget, but it has to gain control of improved economic efficiency can be said that all modifications in the highest. General production car will be fitted with anti-roll bars but mostly confined to the front wheels, the purpose is to reach a compromise handling and comfort.
anti-roll bar is generally fixed at the left and right suspension arms, the centrifugal force acting cause the car when cornering rolling roll center of the vehicle body, leading to the turning inner wheel and suspension tension and compression bending outer , resulting in anti-roll bars extending torsion bar by the torsion repulsive force generated by the shaft of the roll of the vehicle body is suppressed. Here’s “roll” and we previously mentioned “body roll” (Roll) is the same; the so-called “rolling” looked like the car frame in a longitudinal axis passing through the rear from the front from the front direction and then do the rotation. Of course, this rotation is a small margin, if the rotation angle is too large will be overturned, and that is really rolled.
2, action
Sway bars When the same road passing around two projections or holes, and anti-roll bar does not have an effect. However, if the left and right wheels, respectively by different road projection or hole, i.e. the height level of around two is not the same, it will cause torsion shaft, to produce the anti-roll resistance (Roll Resistance) inhibition of body roll. That is when the left and right suspension up and down both sides of the synchronized action anti-roll bars will not play a role only in the right and left hanging because the road is not synchronized rolling or turning movement caused by cornering the anti-roll bar only when an effect. Anti-roll bars only when the role of the road will harden, unlike stiffer springs will complete the road of hard. If you want to completely rely on springs to reduceBody roll that might need to be very stiff spring, but also to use high damping shock absorbers to suppress the spring bounce, so that we will have to bear stiffer springs and shock absorbers caused by nature, such as road, tracking adverse sequelae when passing through rough road. However, with an appropriate anti-roll bars can not only reduce the roll, but without sacrificing comfort and proper tracking of. Therefore, anti-roll bars and spring mix is the most feasible way to reach the road and handling compromise.
3, characteristics
anti-roll bar and the anti-roll bar spring provided complementary anti-roll resistance, and anti-roll resistance occur in pairs, that is to say the front anti-roll and anti-roll resistance is accompanied by the occurrence of resistance to the rear, but because the body weight ratio, and the relationship with other external action will make the front and rear anti-roll resistance uneven, it will directly affect the result of body weight transfer and handling balance. If the anti-tilt caused by the rear wheels oversteer (Oversteer) resistance too large, whereas if the front anti-roll resistance might cause the understeer (Understeer). In order to improve handling we can make use of the scroll bar to control the anti-roll body may be used to further control the ratio of the front and rear anti-roll resistance body distribution. Anti-roll bars to achieve the most important feature is the control of body roll when cornering to improve balance and restrictions attached to the tire. When cornering wheel suspension inturned elongated and curved outer suspension is compressed, then the anti-roll bar will produce torsional suppress this. It will bend the outer wheel suspension cast a downward pressure force, while the inner bend wheel suspension cast a lift force, the administration about the suspension of the force is equal and opposite direction restraining each other. Too soft anti-roll bar independent suspension car would cause excessive camber when cornering, reduce tire contact patch, it is too hard will cause the tire can not be close to the ground, affecting handling. Of the bend wheel, the anti-roll bar to the wheel and the force applied to the spring force is applied to the wheel in the opposite direction, the spring force can be generated by the wheels pushed back to the ground, while the anti-roll bar but make it off the ground. If the anti-roll bar is too hard reduce the pressure back to the wheel? If this happens in the drive wheels, may cause decreases in the draw grip when refueling bend bend wheel, resulting in idling of the tire. ThisFor high-powered cars have not LSD, but is quite dangerous, the ideal state is the anti-roll bar is provided between the anti-roll resistance control 20 to 50 percent of the total percentage of anti-roll resistance. If the total anti-roll resistance is too strong may cause the inner wheel when cornering bend off the ground, so will cause 100 percent weight transfer, which usually occurs in a non-driving wheel of the bend.
We may often see the situation before the turning inner wheel off the ground when cornering Porsche 911, the same situation may also occur within the first bend after the drive wheel. The wheels off the ground is not a good thing, but sometimes to the needs of the overall suspension settings but can not be avoided. Rolling body reduces the sensitivity of steering or tracking. An optimal suspension geometry car is set with a low rolling center, provided by the spring while the anti-roll rolling resistance of the vehicle body can be limited within a reasonable range. Will affect the spring affixed to the tire, the same spring provides resistance to the anti-roll affixed to the tire also has a great influence. There are established for a suspension geometry, center of gravity and vehicle weight of vehicles, anti-roll resistance to change will change the degree of body roll when cornering limit.
4, how to set
If a vehicle when cornering most extreme cause body roll suspension system to produce more than 2 degrees camber (Camber) change, then the vehicle showing portions require more more anti-roll resistance. An excessive body roll when the camber angle changes, it is necessary to increase the representation of at least 2 degrees negative camber angle, the tire so that the tire sufficiently maintained affixed to the limit of the corners. But more than two degrees of camber settings will reduce the car straight into the tire contact patch (Tire Contact Patch), and will destroy the so-called “tracking of the moment” (Transient Traction), which is a straight line from the car to bend or from the moment the flat road to an inclined road surface of the tracking. This handling balance, cornering speed into the corner and out of the corners of the steering sensitivity will have a negative impact, it will affect the bend in the braking and acceleration performance. Another reason for the restriction is to limit body roll scroll Center (Roll Center) of the longitudinal and lateral displacement, which is very important for any type of suspension system, Especially more so for MacPherson’s strut suspension system. The displacement of the center of the rolling body weight can lead to a sudden shift changes, resulting in the destruction of the body handling balance. For the rolling of the car body is limited to within 1.5 to 2 degrees can limit the displacement of the center of the scroll within the controllable range, but generally speaking the road car body roll even limited to four degrees is ideal of. Before and after adjustment proportional distribution of body roll on anti-roll bar setting is very important, if we want to completely rely on springs to suppress body roll
, you must make Heyan w spring, this way will reduce tracking of passing uneven road, if you use anti-roll bars can be easily adjusted without affecting the handling balance of the body of tracking. Therefore racing front and rear anti-roll bars are usually used are adjustable in order to adjust the best handling balance, and general road use are often not adjustable. Drive wheels (rear-drive generally curved when the anti-roll bar are mounted on the front suspension, before the suspension thus be increased when the rear roll resistance, reducing body weight transfer cornering suspension, which may delay or eliminate the cornering inner wheel) away from the phenomenon and to increase the deflection bends the outer wheel load, enhanced understeering tendency. Bold and rear antiroll bars enhances oversteer tendency, the front pair of front wheels in a front wheel drive is because it is necessary to increase the stiffness of the rear anti-roll bars, the tracking result of the increase and decrease of the drive wheels inherent understeer characteristics. But from the roll of the vehicle body is too severe, or if the rear wheel cornering, should be considered the front of the front wheel drive bold anti-roll bar in order to avoid this phenomenon. But on a serious car understeer, it is usually as long as the bold front anti-roll bar can significantly improve the understeer phenomenon.
5, how to retrofit
Sway bars Hardness anti-roll bar is made by the length of material, shaft, rod diameter, and the shaft and the lever arm the angle is determined. The longer the length of the shaft, the hardness of the softer, whereas the longer the length of the lever arm it will increase its hardness. Therefore, the vehicle width is limited by the length of the shaft is almost impossible to change, but the length of the rod diameter and the lever arm is relatively easy to adjust. General anti-roll bar material are similar, so the anti-roll bar to change the hardness is achieved by a change in rod diameter. Also due to the lever principle, and change the point of attachment arm suspension anti-roll bar is possible to change the torque arm lever arm, while the anti-roll bar is adjustable by a start here. In addition, the fixed anti-roll bar rubber pad coffin into hard materials that you have an unexpected effect, the actual test, using a 0.8 inch diameter anti-roll bars coupled with a hard liner and use diameter 1.0 inch rubber pad coupled anti-roll bar having the same effect. Anti-roll bar effect on the performance of the roll when cornering, to understand the best way is to use the camera roll extent photographed when cornering limit, then measure out the roll angle in the photo, replace hard after the anti-roll bar according to the same manner as in make another once, twice compare different angle can be determined. Going to calculate the required anti-roll bar stiffness is very complex, not only to consider their own stiffness but also to consider springs and mix, thus only constant test re-test, which is the only way to set the chassis. When you decide to remodel your chassis, in addition to the springs and shock absorbers with, you should consider to take your anti-roll bar. This knowledge is built on the basis of scientific theory, experience and keep trying, and modified real fun here.