Stabilizer Bars - Do they worth the money?

[NoHachi]

You are mixing stuff up pretty seriously Apolan. ARB's or swaybars are completely different animals compared to strutbraces.

I could give you a complete writeup, but I'm short on time now..sorry. The stuff on howstuffworks is already there but not that good( read, unnecessarily complicated), check it out anyway:
http://auto.howstuffworks.com/question432.htm
for arb's

[Apolan]

i know the exact phisycal aspect of how anti-roll bars / sway-bars / stabilisers affect suspension dynamics; it is the strut braces im unsure of, thats why i ask. The way i see it they just provide the additional rigidity to that part of the chasis, so the "angles" of the chassis remain the same under load, resoulting in better performance of the existing suspension. But i wondered how does that affect suspension performance exactly (like in aproximate numbers)..

[Rasteirinho]

Well, in my car i will fit yellow koni dampers and TRD springs (6 Kg at the front and 4,7 at the rear).

Now, i'm thinking to buy some larger diameter stabilizer bars (or sway bars) in order to decrease the AE86's body roll on turns.

I think i will go for the uprated non-adjustable whiteline sway bars.

Are the adjustable sway bars better than the non-adjustable? Why or why not?

[domi]

Methinks - it just rids you of the body twisting/skewing as you apply centrifugal forces to it. I doubt it'd make more than a centimeter of difference under continuous load and maybe 2-3 under impulse. It is a fact the metal would change shape after time - the strut tower bar on mine is a bitch to take off, but i know it's supposed to fit like a glove - the tops of the struts are constantly trying to decrease the distance between them...
I'll try to hunt for some math on the problem when i come back from work, i'm running late today =(

[Ivan141]

@rasteirinho: adjustable swaybars let you play with the effect of the swaybar a bit so you can find the right setting for your taste. It also allows you a quick method of increasing wheel rates a little for trackdays

[Apolan]

Concerning anti-roll bars. How i think it works: increasig the diameter of the bar ensures that more force is carried to the other (inner) side, as less torsion force is "absorbed" by the bar itself (it twists less because its thicker). Also i think the fatter bar gives quicker response. But too fat the bar - and you loose the independace of the front wheels. But this cannot be adjusted obviously - you pick the thickness you want.

Now the adjustable part is the lenght of the "lever". Holes are drilled at various distances. If you imagine a basic sway bar shaped like this -> l__________l -> then the lenght of "l" is your lever over which torque is transmited via "____________" to the other side. Now hereh is the part im unsure of (see the pic now).

So actually shortening the lever means more torsion tension in the transverse bar, less flex due to smaller torque, resoulting in more force transmited (more compression on the other (inner) side) and quicker response?

Is this correct?

[domi]

The shorter the transmitter arm - the harder it is to bend, ergo you get a stiffer bar and a closer ratio of travel between the two wheels, the longer it is, the easier it bends, so the difference is bigger. That would be my logic which has been known to be inacurate every now and then =)

[NoHachi]

Nopes its correct.
@Rasteirinho: don't pay extra for adjustable sways if you are not going to play around with them. Swaybars in general are a tuning tool: just a quick way to play around with springrates. The number of people that, like me, start to nerd around with tire pressures, swaybar settings etc is rather small, so the non-adjustables will be fine.

[dr.occa]

they're worth the money.

bascially, you're just wanting to reduce body roll. unless you're going to be willing to put work into tuning in/out the right amount of body roll, don't bother with the adjustable roll bars and save your money and get decent aftermarket bars (e.g. cusco). it really all depends on what you want the car to do at the corners. less body roll is going to be better than stock body roll though . they will bring the car more under your control and usually that should be good (depending on the nut behind the wheel). the more stable and sure-footed you are in a corner the more confident you'll be in your driving. And the more confident you'll be, the more relaxed. This is a good thing.

[NoHachi]

Roll bars are about as low tech an item as they come. Its a metal tube and it bends. Monkeys could fabricate them. I would say that arb's are one of the few items where you can get away with cheap stuff. Just make sure that the mounting hardware allows the bar to rotate freely. Even the Cusco stuff rarely does this right away, so spend some time to get that perfect (just some patience, sanding paper etc are needed.

I'll keep hammering on this:
ARB's reduce roll because they are springs. They do exactly the same thing as springs but only during cornering. If someone gives me a couple of measurements I can say exactly what the influence of diff arb's is on the wheelrate.