Sway bar
Control Arm
Stabilizer Link


Why do you need an aftermarket sway bar?

A short explanation of why you need an aftermarket sway bar is that it helps improve your vehicle’s handing and gives you, the driver, more control of the car. For example, if you're taking a right hand turn at high speed, the car begins to lean to the left and put more load on the left side tires, whereas the tires on the right hand side of the car start to lose contact with the road surface. Because of this, they aren't able to work effectively and efficiently in getting the car to rotate through the turn.

What is Anti Roll bar stiffness equation

How does a sway bar work?

Following the law of inertia, an object in motion wants to stay in motion unless acted upon by an outside force. In this case, the outside force to your vehicle is a change direction. As the mass of your vehicle corners, its inertia is causing the car to "roll" to the outside of the turn. This rolling affect causes the car to become unbalanced and "unplanted." The purpose of the sway bar is reduce this action and keep the body of your vehicle level, while maintaining traction and control as the weight is shifted from side to side. The transfer of loads through the sway bar can improve your vehicle’s handling?

Does your Sway bar come with bushings?

With only a few exceptions all sway bar kits come with bushings. Kits that do not have bushings are designed to mount without them.

Is a bigger sway bar diameter better?

Many customers fall into the ‘bigger is better’ trap and shop only for the largest sway bar they can find. Sometimes this works, but many times they are compromising their vehicle’s performance. If other modifications have been made – increased spring rate, lowered height, change in roll center, etc. – the best sway bar may be smaller. The vehicle is a combination of its parts and it doesn’t care how massive and cool the bar may look, it only cares how the sway bar interacts with the rest of its components. This is why our produces adjustable sway bars for many applications. The adjustable sway bar allows you to tune the vehicle to your driving style and suspension components. We also manufacture more than one diameter for popular applications to allow the customer to match the right sway bar to the vehicle.

What is an ideal sway bar setup for oversteer?

A “softer” setup in the front would encourage a good turning ability. The fact that the weight transfer puts a good deal of pressure on the outside tire and rotates around the corner. Meanwhile a “stiffer” setup in the rear will allow more minute losses of traction and a responsive rear end. This also helps rotation around a corner.

Why choose the sway bar from YZS?

We are a professional sway bar supplier of aftermarket and performance in China, with 15 years experience in this line. As a modern enterprise, it has a complete system of R&D, production, sales, service and also has a strong technical and management team. Give us a try and turn your curiosity into an obsession.

How can I calculate the over-steer or under-steer due to the anti-roll bar?

There's this great book called Fundamentals of Vehicle Dynamics by Thomas Gillespie. Chapter 6 of that book deals with cornering. The term he uses to describe cornering of a vehicle is steady state cornering. In the book, the equation for steering angle is given as follows,Steer Angle = 57.3 L/R + K*(lateral acceleration) where: L = wheelbase R = radius of curvature of curve K = understeer gradient (+ve if the car has understeer, -ve if oversteer, 0 if neutral). An anti roll-bar is a part of automotive suspension that is used to reduce vehicle roll by stiffening up the suspension. So basically, it transfers the lateral load generated due to cornering.  Now, understeer gradient is the ratio of load on axle to cornering stiffness, i.e., W/C. When both ratios for front and rear axle are equal, it is termed as neutral steering (K=0). When the ratio of front is greater than the rear, it is termed as understeering (K0). When the ratio of front is less than that of rear, it is termed as oversteering (K). Since, lateral force (a) = W (V^2)/(C g R)where, g = acceleration due to gravity andV= forward velocity,we can predict whether the vehicle is going to understeer or oversteer by calculation and equating W/C ratios for front and rear and make necessary adjustment to the steering angle to compensate for the same.

What are car control arms and what is the average cost of replacing them?

Control arms are part of the suspension which locates and controls the movement of the hub and strut. There are usually a couple control arms on each corner of the vehicle. They also have bushings and ball joints which is usually why they need replacement ovetrtime, since those are wear items. The cost to replace varies depending on the vehicle. Control arms cost different amounts depending on the vehicle, as well as the labor to install. Some are easy to install and take little time, while others can take several hours.

Do I need to replace the control arm if the bushings are worn? What is the safety risk?

Likely the replacement control arm comes with new bushings, although I'm not an expert in that particular car.  Most come as a unified assembly these days, and for a car as widely produced as the Accord, you could probably replace the entire unit for cheaper than just replacing just the bushings, but I'm not an expert in that particular car. Its always worth it to replace bushings on control arms.  I wouldn't mess with anything that has to do with integrity of the front suspension, unless you live somewhere where the roads are perfect and pristine, you never have to make evasive maneuvers, and you don't ever turn.   It also can substantially effect the front end alignment, depending on how worn it actually is, which effects how straight the car goes on the highway, and how well it responds to steering input.Front ends, while really sturdy, need to be intact to be operate as designed.   I realize you may not want to spend any money on it and want it to last another year, but its an  unfortunate false economy to not replace a control arm bushing.

Where should anti roll bars be used in f1 type cars?

It depends on your kinematic set up and your computed values like for example one of it could be the roll stiffness'.I wouldn't spoon-feed you on this as you've to understand it on your own before following someone else's advice whether to use it or not and where. This would eventually help you in many ways. You'll be in a position to firmly assert your decision in the Design Report, which I feel is the most important part of the competition and you would be totally accountable for the dynamics of your car. It would give huge returns in the testing phase while playing with stiffness and other parameters.I would urge you to read fsae forums and other books like tune to win- Caroll Smith, Race Car Vehicle Dynamics (RCVD)- Milliken and Milliken, technical papers published by Optimum G (Claude Roulle's company). After reading all these things, infact from RCVD itself you would be in a state to conclude where to use in your car (Obviously you will have to brainstorm and take an informed decision considering your driver's skill, engine power, aero/noaero, etc).There are many cases on FSAE forums.And lastly, I would request all of us to not post a cliche question on fsae forums without a proper protocol (name, university name, team name, and proper description of your situation) which you'd find in the answers and questions there. It just spoils the name of Indians and the one starting the thread with the question is abused very badly.You'd think why this is important?Because if you go to an international competition you come to know the situation and how they misconstrue us and we would obviously not want our nation and fellow students to let us down at an international level!

What is the main difference between a torsion bar and a anti-roll bar in vehicles?

Both the Anti Roll Bar and Torsional Bar / Torsion beam work on the same principle - torsion or twisting of a beam to provide an elastic mechanical connection between opposite sides of a suspension.I've differentiated between Anti Roll Bars and Torsion Beam Axles in the following sectionsAnti-Roll Bar ( henceforth referred to as ARB )As the name suggests, an ARB prevents excessive sideways tilting movement (Roll) of the vehicle while taking turns. The anti roll bar is usually a thin and shaped bar that connects two sides of an independent suspension system ( mostly used in the front wheels ) so that when one suspension moves up or down, the movement is PARTIALLY transferred to the other wheel too and thus helps maintain a mechanical connection with flexibility ( due to torsion ).An ARB is also referred to as a Torsion bar sometimes. The ARB is attached by means ofpin joints or ball joints to the suspension linkages on either side and by means of bracket mounted pin-joints to the under body of the vehicle.These linkages are a key difference between Anti Roll Bars and Torsion Beams. Torsion Beams are typically welded to the trailing arms of rear axlesCouple Torsion Beam Axle / Twist Beam Axle (henceforth referred to as CTBA )A CTBA is a much thicker formed metal beam that is welded to a set of  trailing arms. The torsion beam acts as a flexible mechanical link ( similar to the anti roll bar ) with a high torsional stiffness compared to the anti-roll barSince the CTBA is welded at both ends , it allows for a significantly lesser range of relative movement between the two trailing arms. CTBAs are used in rear suspension in tandem with coil spring and damper systems in small cars and other entry level sedans.

How long will it take to replace the front sway bar?

The front sway bar is a little more difficult than the rear sway bar install.But it isn’t very hard at all. The only reason it takes longer is because you have to remove a couple of trays, so it still won’t be a problem. If you are performing this upgrade yourself and you have the proper tools then this job shouldn’t take more than 1-1/2 hours.

Why don't many convertibles have roll bars?

Most modern convertibles have roll bars.They are deployed through the convertible top/bodywork/rear seats in a fraction of a second when sensors in the car detect that the cars pitch has transferred to a dangerous angle.Some cars are offered with optional roll bars (think Mazda MX-5) that are attached to the frame of the vehicle and protrude out of the vehicle. When fitted, these roll bars replace the factory system, which is then either removed or deactivated. The obvious benefit to this addition of aftermarket rollover protection is the reduction in weight of the motors/electronic assembly associated with the OEM units.