sway bar questions

[Erik]

Hey guys,
I have a few questions regarding sway bars since i dont know too much about them. Is it still beneficial to have only a rear sway bar or just a front sway bar? Is it a better option to wait to buy both? If buying just one at a time, which would be a smarter start?

thanks for understanding that im a noob

[Spocknasty]

Just buy a rear. Adding one to the rear encourages oversteer. Adding one to the front encourages understeer.

[Erik]

so then would having cancel eachother out and leave back at where you started? or would handling improve?

[Kevin]

Does it matter if your car is awd? I've always wondered this. I think I remember reading an article about sway bars affect awd cars differently.

[Spocknasty]

"f you don't have a stabilizer bar, you tend to have a lot of trouble with body roll in a turn. If you have too much stabilizer bar, you tend to lose independence between the suspension members on both sides of the car. When one wheel hits a bump, the stabilizer bar transmits the bump to the other side of the car as well, which is not what you want."

"Anti roll bars provide 2 main functions:

The first is the reduction of body lean. The reduction of body lean is dependent on the total roll stiffness of the vehicle. Increasing the total roll stiffness of a vehicle does not change the steady state total load (weight) transfer from the inside wheels to the outside wheels, it only reduces body lean. The total lateral load transfer is determined by the CG height and track width.

The other function of anti roll bars is to tune the high g / limit understeer behavior of the vehicle. The limit understeer behavior is tuned by changing the proportion of the total roll stiffness that comes from the front and rear axles. Increasing the proportion of roll stiffness at the front will increase the proportion of the total weight transfer that the front axle reacts and decrease the proportion that the rear axle reacts. This will cause the outer front wheel to run at a higher slip angle, and the outer rear wheel to run at a lower slip angle, which is an understeer effect. Increasing the proportion of roll stiffness at the rear axle will have the opposite effect and decrease understeer."


"Because an anti-roll bar connects wheels on the opposite sides of the vehicle together, the bar will transmit the force of one-wheel bumps to the opposite wheel. On rough or broken pavement, anti-roll bars can produce jarring, side-to-side body motions (a "waddling" sensation), which increase in severity with the diameter and stiffness of the sway bars. Excessive roll stiffness, typically achieved by configuring an anti-roll bar too aggressively, will cause the inside wheels to lift off the ground during very hard cornering. This, of course, is only possible if the regular spring rate actually allows the outside wheels to handle the much increased load."

Just get a sway bar for the rear. Go with a nice beefy strut bar for the front.

[Erik]

Sounds good to me.
Does this apply differently to each driveterrain? The car im talking about is FWD.

[gary]

FWD cars have understeer from the factory. Adding a rear sway bar will decrease the understeer tendencies. How much it decreases will depend on the diameter and stiffness. Your ultimate goal with a FWD car would be to have just a tad of understeer but so little that you will usually break all wheels free at the same time. Oversteer in a FWD vehicle is pretty much useless since you can't control it like RWD vehicles.

[Erik]

Gotcha. Thanks guys

[99SL2_Modder]

Yeah, the rear swaybar on my car upgraded the stiffness of my suspension (well,along with the poly bushings that tightened it up) by about 310% or so. With factory alignment, I couldn't keep the bitch from doing 180's and sometimes close to 360's on hard turns. Definitely be careful of what you do, and compensate a little for it. I have that issue fixed, but I need a little bit more rotation, so I'm dropping my front swaybar down to the lesser version of my car. (about 2mm smaller). My car came with both front and rear.