Stabilizer Bars - Do they worth the money?

[Apolan]

what are the rates of stock ae86 stabiliser bars? Lets say they are cca 10 kN back and 20kN front.. is that anywhere close and what is the influence in this case? Do they add 2kg/mm of springrate in front in this case?

[oldeskewltoy]

NoHachi Wrote: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.

One thing you may not have accounted for.... materials used... also solid or hollow.....

[gt99]

I dont have any experience with ARBs, but I think they affect suspension stiffness. Is it right?

And I read that ARBs are just "secondary springs", and racing cars theoretically don't need them. Only serious advantage is adjustability. Its easier to change ARBs setting, than change springs.

BUT ae86 are old cars with week body stiffness (no problem with roll cage equiped racecars), and stiff springs can damage body. So ARBs can be usefull for ae86 owners.

I could be wrong, so correct me.

[Mux213]

gt99,

That isn't totally true.. The big difference between arb's and springs is that arb's add spring on body roll. So if you aren't cornering and you hit the brakes or go over bumps in the road, the arb's are doing absolutely NOTHING.

But when you are cornering then suddenly they show their effect. This means you can tune the handling in cornering of your car with arb's without changing the characteristics of the car during braking, acceleration or driving on rough roads.

[Apolan]

Mux213 Wrote:So if you aren't cornering and you hit the brakes or go over bumps in the road, the arb's are doing absolutely NOTHING.

I have read that if you put to stiff arbs, they influence the independance of the left and right suspensions, so when you go over bumps, having to stiff arb, would yield in some negative effects/loss of traction?

[gt99]

Mux213 Wrote:gt99,

That isn't totally true.. The big difference between arb's and springs is that arb's add spring on body roll. So if you aren't cornering and you hit the brakes or go over bumps in the road, the arb's are doing absolutely NOTHING.

ARBs don't do anything, if left and right wheel on axle do the same movement. Mostly braking, accelerating and maybe speedbumps. But if you go on bump with one wheel, I think ARBs will work.

My english isn't so good to explain further, sorry.

[domi]

Exactly. Let's say you're looking for a good suspension setting for a daily drive and need the softness and travel as you very much will, but you don't like the roll, or say, your suspension is bottoming out when you take your favourite corner on the highway ramp with the speed you like - you put on ARBs and you're set.

NoHachi, let's say a guy goes for a 6.5/4.5kg/mm spring rates f/r, with some aftermarket non-adjustable dampers, like tokico, what would be a good rollbar combo for front and rear if you're looking for streetable, part-time-trackable car?

[assassin10000]

On my last 86 I ran 6kg front 5.5 rear for daily driver comfort. With whiteline adjustable sway bars front & rear.

The front was set at 3 which should equal about 26mm and the rear was set at 4 which should be about 22mm (roughly, sway bars differ in materials, hollow/solid and actual torsional strength)

I was pretty happy with it, but once I started hauling ass around a 3rd gear bank and 70+ mph I realized I need to go to slightly stiffer springs

http://video.google.com/url?docid=-73440...DXnbybStWg

http://video.google.com/url?docid=-11499...GDk5DToPUA

Andrew

[NoHachi]

oldeskewltoy Wrote:One thing you may not have accounted for.... materials used... also solid or hollow.....

Material used is "spring-steel" (dunno what the correct English term is). 90% of the ae86 bars will be solid, but calculation is mostly the same between hollow and solid bars, just different way of calculating the polar moment.

@domi:
On a smooth track surface (not all tracks are like this), You can get away with the arb's coupling effects..hell ae86's have a solid axle in the back any way, so who cares. You can get a pretty nice dual use setup if you take the thickest arb's that you can find. Get a set of springrates that suits your daily driving and doesn't need arb's for balance. At the track, reconnect the arb's and jack up the shocks. For trackdriving you want a slightly higher front roll couple (more understeer bias), so probably just the front bar would do. For drift practice add a thick rear bar too. To make any significant difference you would really need the stiffness of a hollow front bar.
Otherwise, just add a set of solid sways and be done with it, they wont hurt daily driving that much, certainly not in the USA. I'll throw down the calculations (simple ones) for arb stiffness this afternoon, so everyone can get a relative feel for the difference. I would need suspension geometry data to calculate wheelrate and equivalent spring rate, so that will take a while.

[domi]

Thanks for that, we're ready for those calculations whenever you are

Seriously, take your time, i have to deal with more issues on my car before i reach the suspension tuning, so i have all the time in the world. What kind of setup are you running on your car [and if it's not a hachi - what is it, what's the difference in weight and weight-distribution]?