[jgalaxy]

Has anyone tried the UUC Swaybarbarian front and rear swaybars? I havent seen any feedback anywhere and was curious if anyone has tried this kit ...

[jimmy330xi]

I think Longodj posted a review in the Group Buy thread.

[jimmy330xi]

Here it is
http://www.e90post.com/forums/showthread.php?t=150049

[wakeboarder109]

Damn, these look like they are worth the money. Anyone see a group buy?

[cyphr]

I've been running their f/r kit. Unlike longodj, I feel like these sway bars introduce more understeer to an already understeer prone setup. I've talked with Orb and he agrees that the front bar is way too stiff for our XIs. Some people get the impression that since these bars are significantly stiffer than stock, that the car handles better. Stiffness does not equal better handling.

I'm working on finding a solution which is either removing the front sway and replacing it with a narrower bar or upgrading the rear bar to h&r (thicker).

[jgalaxy]

Originally Posted by cyphr

I've been running their f/r kit. Unlike longodj, I feel like these sway bars introduce more understeer to an already understeer prone setup. I've talked with Orb and he agrees that the front bar is way too stiff for our XIs. Some people get the impression that since these bars are significantly stiffer than stock, that the car handles better. Stiffness does not equal better handling.

I'm working on finding a solution which is either removing the front sway and replacing it with a narrower bar or upgrading the rear bar to h&r (thicker).

Thanks Cypher. This was what I was anticipating based on some of Orb's input and this confirms it. We'll have to wait for some front end suspension magic developed by some other vendors. So far I've ditched the staggered setup on my KWv3, stiffened the front dampening (I think conventional wisdom says to the opposite) and added as much negative camber up front as possible to get ride of the understeer. Getting there. Can you share any added insight to get rid of the understeer?

[who's ur daddy?]

So can you just get the stiffer rear then and leave the front stock?

[jgalaxy]

I think the conventional wisdom on a stiffer rear alone is just going to cause more understeer and possibly some lift on your inside rear wheel with accompanying wheel spin. This assumes KW installed.

I'm thinking we need to collect the data that's been shared by sharper minds and request a sticky.

[louie_perm]

I've been doing some reading--to the extent I can find any. Orb is a little hard to follow sometimes--no offense, Orb.

All else equal, stiffening the rear bar should reduce understeer by decreaing the traction of the rear relative to the front. Stiffening either a bar or spring has the effect of reducing traction because you are hindering the wheel(s) ability to move in response to variations in the road surface.

The relatively stiff front of the Xi is the reason for the understeer. KW coilovers (a set of which I'm putting on next week) have softer springs in the rear relative to the front, as compared to stock. Hence, Orb's suggestion that stiffer springs in the rear are needed--this could be considered the "purest" fix.

What is not clear to me is the interaction of the bar and springs. Both affect traction. However, I don't think bar stiffness is a perfect substitute for spring stiffness. If they were good substitutes, then simply stiffening the rear bar would seem to fix the issue with the softer rear springs. But, my guess is that can only go so far--the softer springs/stiffer bar combo would likely have its own consequences.

If anyone wants to jump in here and explain further...

[louie_perm]

Did a little more reading this weekend. Let me refine my earlier comments.

Stiffening one end of the car (front or rear) causes more of the weight transferred in a corner to go to the stiffened end of the car. The increased load reduces the cornering efficiency of the tires on that end of the car.

Therefore, stiffening the rear will cause more weight to be transferred to the rear (and less to the front) during a corner, thus reducing the cornering efficiency of the rear (and increasing the cornering efficiency of the front), i.e., reducing understeer.

Body roll, itself, does not cause weight transfer in a corner (at least not much of it). The effect of body roll is to change the contact patch of the tires by causing positive camber as the suspension adjusts to the roll. Stiffer springs and/or sway bars are used to combat this effect.

Absent the body roll considerations, the best spring is the one that is as soft as possible without bottoming out.

The compromise, then, is to find a happy medium where the ride is compliant (soft) enough to allow the tires to follow the variations in the road surface, while at the same time being stiff enough to avoid excessive body roll in a corner (as well as excessive brake dive and acceleration squat, neither of which is affected by the sway bar to the extent they are evenly distributed side-to-side).

I haven't found many discussions of the relative merits of springs versus bars to combat roll. The one or two I've seen seem to recommend relatively soft springs with the sway bar being used to compensate and combat roll. I've seen nothing that specifically addresses the relative stiffness of springs and bars, like whether there is some ratio between spring and bar rates that is "ideal."

[evo911]

i just got them on along with reinforced control arms, kwv3, camber plates, and clutch will see how the car is

[jgalaxy]

Originally Posted by evo911

i just got them on along with reinforced control arms, kwv3, camber plates, and clutch will see how the car is

Which manufacturer did you use for the control arms?

How is the rideability, turn-in and roll?