Have a set of cusco sway bars with tein flex suspension (10kg springs) and was wondering if someone could help out. What i'm finding is that with the sway bars fitted I have either less traction in the rear or one wheel is lifting off the ground. I find that I start going sidways easier than with the oem sways.

Any ideas or suggestions. Would a 1.5 LSD help.

I'm also running a HKS SC so a little bit more power than standard. Tires are S03's front and rear.

 

wider rims and more rubber! it makes a world of difference plus it will look better.

 

when was the last time your car was aligned? what size wheels/tires?

 

The fronts are 245/40/18 and rear 245/45/18.

The car has been wheel aligned recently. From memory I think it is just under -1.2 camber on the front and -1.5 on the rear.

I agree wider rubber would help but I really only noticed this after the sway bar install.

cheers,

 

unfortunately there are lots of things this "could" be......improper alignment strikes me as being the first, or your sway bar settings, damper settings, tire pressures...all have a huge effect on traction

 

Z1, I agree any pointers.

Pressure in tires is 34 psi. Damping rate is set to soft side. (testing to see if it was too stiff in the rear)

Swaybar is one setting only on the rear so no adjustment their.

 

see if you can get a printout of the full alignment specs...might reveal something

also, under what conditions does it do this?

 

Also make sure your ride height is precisley the same...left and right. You really should have your car corner weighted/balanced with you in the car. If there is more weight on the left side of the car, it will be challenging to get a linear pull.

An LSD will also help you hook-up cleanly off the line.

 

a rear swaybar on the stiff setting will also promote oversteer.. are you sure it's a loss of traction and not oversteer that you didn't have before? or do you also have less traction in a straight line?

I'm betting on a combination of soft coilover setting at the rear and a stiff swaybar.

 

I think he is refereing to traction and stability in a straight line. Correct me if I am wrong, but does the swaybar affect traction in a straight line as well?

 

I'd say so.. just like anything that reduces flex in the chassis but I doubt it's a considerable difference since the Z has a rear swaybar stock. It does make a huge difference in the turns though, since now you're playing with the amount of understeer/oversteer etc.

When he said "one wheel is lifting off the ground", I assumed he's talking about traction in the turns. My GTI would lift it's rear wheels easily 5" off the ground, crazy sight!

 

Large rear sways can result in inside rear tire lift. If this is your problem you need a "smaller" rear sway or a "larger" front sway

 

Thanks for all the replies.

The issue is not in a straight line but when cornering. The reason I fitted the swaybars was to introduce a bit of oversteer. The settings that are set currently is the stiffest on the front ie 137% and 173% on the rear. Maybe it is me and not being able to control the oversteer correctly but I just feel that I cannot carry enough exit speed out of the apex without the rear end stepping out hence why I'm guessing that the inside wheel may be lifting.

The car is going to be wheel aligned again this saturday and will let you know of the specs

 

I have had a similar issue, The rear sway is stiffer than optimum . Yes it does increase understeer , but it also locks the rear suspension together (less IRS action), which can cause more un-wanted inside rear tire lift, epsecially on rough pavement.

 

Yup, definitely sounds like your rear sway is too stiff. Which bars are you using? Sounds like Cusco. Since it doesn't have any adjustment try going back to the stock bars and see how that feels. Ideally, you want to use springs as the primary source for lessening body roll and setup understeer/oversteer balance. Sways are more secondary and are meant to fine tune the balance. That's why I would only purchase a set of sways that are adjustable. That way you can fine tune them to your liking no matter what suspension setup you get.

 

I would say you probably need a more aggressive camber, a good alignment/ corner balance. Secondly, you need bigger tires in the back and probably some R compounds

Oh and to answer your question a LSD will help as well. I know it made a huge difference for me and I am NA. With more power it would be a necessity

 

What I'm hoping with this alignment is to reduce the amount of camber in the rear and also the toe. I believe these two will increase the contact patch of the rear tires.

I also stiffened up the rear damping which has seemed to help but still need further testing.

Michael

 

IMO, the rear setting is definitely too stiff. I found the rear wheel lifted too much when I ran my Hotchkis rear sway at full stiff (146%). Med (92%) is the most I'll go and I usually prefer the lowest setting (54%).

In playing with various spring rates, I also found my 350 liked a really soft spring rate. Until I recently took my JIC kit off, I was running 12kg up front and 9 kg in the rear.

Don't forget that sway bars can increase the spring rate. I found that running the rear sway too stiff negated some of the benefits of running the softer springs in back (which effected corner-exit traction).

 

agreed to an extent.....everything has to be working and setup together to get a truly neutral/good handling car

I am on the Cusco sways....with S03's (staggered 18's) and Cusco coils...the inside wheel does not lift now, but at a certain point, it did. By increasing the preload on the rear spring and softening up the dampening a bit, as well as dialing in the proper toe, I eliminated it completely.

 

Z1

Silly question. How did you increase the preload on the rear without affecting the ride height? I understand how you can do this on the front since the height can be adjusted by the bottom collar but on the rear the shock and spring are separated.