I have a Whiteline front sway bar that i'm going to put on the stock endlinks. Can i take the preload out by having the car on jackstands and then jacking up the control arms until it is near stock ride height or is it better to have the car on a lift with all four tires on the ground? I don't have a lift and was wondering if jacking up the control arms to take the tension out would work. I want to do it the proper way but i'm confused.

Thanks

 

Bump

 

Lower it onto some ramps or something to load the front suspension and you'll be good to go.

 

Swaybars are not loaded when the car is level and not in motion, nor are they loaded when both wheels are suspended in the air. You don't need to "load" the suspension for a sway bar install the way you do with coilovers.

However, jacking up one corner at a time and/or loading a single control arm WILL put load on the bar, and make it impossible to install it. So even if you wanted to load the bar for the install (which you do not), you wouldn't be able to do it anyway.

 

When you say, "nor are they loaded when both wheels are suspended in the air," you mean when both front tires are on ramps or something, right? So what is the proper way to install the swaybar? I am asking for the correct method whether that be using jacks, ramps, or whatever.

 

Give this a look. I pretty nice write up on install.

http://www.robrobinette.com/S2000SwayBar.htm

 

Ideally you'd have both left & right wheels on a ramp (just the axle you're installing, don't need all 4 wheels). This is static height where the left & right heights are not moving relative to each other.

Without ramps, you can jack up that end so that both wheels are off the ground. At full droop, the 2 sides are approximately at the same height, so there should be almost no preload. I did this with my S on stock springs just fine.

On some other cars where the left and right sides don't weigh the same, but come with identical spring rates, then their side-to-side relationship at full droop is not the same as when the wheels are loaded (on the ground/ramps).

 

What exactly is preload? Is it how each side is tightened relative to the other when on jackstands which puts a stress on the bar towards one side when the wheels are back on the ground? Or is it when the bar is torqued on while the car is lifted on jackstands and then when all the wheels are back on the ground there is tension in the bar because it wasn't tightened with the load on the tires?

 

Having preload for a sway bar means at static height (car standing still on level surface), there is tension in the bar.

Imagine a good quality sway bar outside the car, and the 2 end holes are at the same level, there is no preload. After you install the bar on the car, for whatever reason those 2 holes are not in line, then you already have some minor bar twisting going on. That's preload.

It's about the height of one end hole relative to the other. So to avoid preload, you want to install the bar when the wheels on 2 sides are at the same height relative to the body. One way to achieve that is installing with wheels on ground, which can be hard to reach. Another way, much easier, not as perfect, but usually good enough, is to let the 2 wheels/hubs fully hang in the air, so that the height of sway bar mounting points are about even.

 

There are so many variables that must be controlled in order to actually eliminate any anti-roll bar preload that it's not worth it for any street driven car. It's also not a first order (or even second order) effect. Most people wouldn't be able to tell the difference even if the process was completed properly. Don't waste your time...but that's just my 2 cents.