Okay… so you broke/bent an end link and you have to detach your swaybar to keep things from thunking around. You drive around for a bit and you don’t notice any difference… what’s going on? Did Hyundai just install a part on your car that you don’t need? What does a sway bar do, anyway… and do you really need one?
What is it and what does it do?
A sway bar, also known as an anti-roll bar, roll bar, anti-sway bar, or stabilizer bar, is the part of your suspension that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. In essence, it does this by connecting the left side of the suspension to the right side of the suspension to reinforce the side that is being compressed.
As far as what does it do, it resists the body’s tendency to shift weight in a turn which can cause a wheel to lift and increases grip by balancing the lateral stress on the tires by reducing the weight shift and compressing the opposite side’s spring. Uh.. what? Just look at the picture below…. it prevents that from happening…
Notice how very little weight is on the inside wheels of the vehicle depicted in the picture above? When a vehicle has excessive body roll, the majority of its weight is shifted to the outer tires during a turn, causing less weight to sit on the inner tires. 
A sway bar’s purpose is to keep suspension movements relative throughout turns. This means that when the vehicle makes a right turn, the left side of the vehicle’s suspension will compress similarly to the right side, keeping more weight on the inner tires and as a result, increasing grip. More grip = higher speeds = no sliding.
Can I run without a sway bar?
The short answer here is, “yes”. You can drive your car just fine without a sway bar. You can even corner without a sway bar. The sway bar’s purpose is to stabilize the car in turns… but that doesn’t mean you have to have that stabilization all the time. What the sway bar allows you to do is to take turns faster without losing lateral grip. For normal, everyday driving, chances are that you are not taking turns that fast anyway. Most average consumer cars do not even have a sway bar installed. Certain aftermarket struts can actually do the same thing as a sway bar by automatically stiffening/softening the ride of individual struts to balance the car in a turn.
A word about adjustable front endlinks…
The endlink connects the lower end of the front strut housing to the sway bar on each side of the suspension.
Some aftermarket coilovers reduce the overall height of the strut by reducing the length of the shock body. If the OEM length endlink is used, it will push the end of the sway bar down. Ideally, you want to keep the end of the sway bar parallel with the ground when the suspension is loaded (car is on the ground), which means if your coilover reduces the overall length of the shock body, you need to reduce the overall length of the endlink that attaches the shock body to the sway bar. Many aftermarket coilover companies that make the strut shorter by shortening the shock body will include shorter endlinks with their kits… some do not. If you need a shorter endlink and one was not provided in your kit, you will need an adjustable endlink.
The advantage of adjustable height coilovers vs fixed coilover struts is that the ride height of the car can be adjusted. This enables another performance adjustment (other than lowering the center of gravity of the car) to be performed… and that is corner balancing the car. A car is corner balanced to shift the weight of the car front to back or side to side in an attempt to ensure that each wheel holds exactly the same weight when the car is sitting static with the driver in the car. Balancing the car makes the handling more predictable and reduces the tendency to oversteer or understeer. With that said, the likely scenario is that one side of the car may be adjusted higher than the other side in order to shift weight. What this means is that one side’s strut is compressed more than the other and the sway bar gets “loaded” because it is trying to compensate for the loading of the lower side. Adjustable endlinks are used to “unload” the sway bar by adjusting the length of the link to relieve tension on the bar. If you corner balance your car, you really need to have adjustable endlinks because the sway bar can undo the effect of the corner balance by compressing the side of the car that needs to be higher in order to shift weight.
Things that an adjustable endlink won’t do for your car:
- Adjustable endlinks won’t make the car handle “better”
- Adjustable endlinks will not make the car feel “more stable”
- Adjustable endlinks will not make your car handle turns better (unless you are corner balanced)
- Adjustable endlinks will not make your car handle bumps better
There are a number of vendors out there that will attribute magical properties about their adjustable endlinks simply because you can adjust them… don’t believe the hype. The majority of people out there don’t really need adjustable endlinks and they will not improve your handling if you had them. Also, keep in mind that every vendor has its “fanboy” following… those people who so believe in the product or the vendor that they will exaggerate the truth in “testimonials” and talk about how they feel about the product rather than producing objective evidence of actual performance gains. Don’t fall for the trap. If you need adjustable endlinks, you’ll know that you’ll need them.
NOTE: Don’t confuse adjustability with “beefiness”. A heavier piece of metal will be able to withstand more stress than a lighter piece of metal made of the same material. Folks who are running with “beefier” aftermarket sway bars that do not have as much flex as the OEM sway bars will put more stress on their endlinks and the OEM or even most aftermarket endlinks can and do bend under these conditions. You can get “beefier” endlinks without having to go to adjustable endlinks… Moog makes “beefier” front endlinks for the Genesis Coupe at a fraction of the price that some vendors charge for their “beefier” adjustable endlinks.
The last bit of advice with regard to adjustable endlink I offer is to make sure that you only adjust your endlinks with the suspension loaded. If you adjust your endlinks when the car is in the air (no weight on the wheels), you defeat the purpose of having adjustable endlinks because when you put the weight of the car back on its wheels, your endlink will move the swaybar from the position you set it at. If your car is lowered, it may be impossible for you to reach the endlink to adjust it… so you really need to have your car on a drive-on rack or over a pit that keeps the weight of the car on the wheels if you can’t crawl under it when it’s on the ground.
