Swaybar decision

[Hijacker]

So I'm sitting here trying to decide what swaybar I want to put on the rear of my car. One of the big problems I've been having lately in auto-cross is that the car just doesn't want to rotate around and has too much understeer. I'm planning on helping reduce the issue with a larger rear swaybar, but I'm up in the air as to what bar I want to use.

the Whiteline bar is first up on my choices. It's only a 22 mm bar, which is a big improvement over the 17.5mm rear stock bar.

for an additional amount of money, SPL has largus swaybars that have a 27.5mm rear bar.

My big conundrum is that given the massive understeer qualities that the car has exibited on the auto-cross track,and the extra weight of the convertible, would it benefit more from the larger 27.5 bar, or would the softer 22 bar be better. The whiteline bar does have adjustable lever arms, whereas the largus bar doesn't get any adjustability.

Some insight would be wonderful guys.

[94_240sx]

What is your tire setup and what kind of tires are you running? There are so many factors and variables, so more info would help. I'm also in the market for a set of swaybars. This is a recent thread about swaybars. It's good.

zerothread/211723

[Hijacker]

my race tires are a 205/50 on 15" wheels. God I haven't even looked at them in so long, I forget if that's the proper sizing. I'll double check em later.

And I didn't really reply to that thread in particular because amoeb and naed were getting heavy into the theoretical aspect of it all. I didn't want to disrupt the flow they had going.

Also, their info is excellent, but just being a slightly heavier car throws yet another variable in there, and this was something directed at thoughts of people who have actually tried the products I listed on our cars.

[biggie]

Find R32 GTR sway bar. I did.

[94_240sx]

Find R32 GTR sway bar. I did.

What's the difference between R32 and s13 HICAS swaybars. Do you know by chance?

[94_240sx]

tenkawa,Do you have coilovers? If so what's the spring rates front and back?

[biggie]

What's the difference between R32 and s13 HICAS swaybars. Do you know by chance?

Rear GTR stock sway is 26mm. Can be pretty hard to find, people in Canada should have them though.

I have pretty good balance with the tanabe sway bar in the front (30.4mm), although my alignment hasn't been great for a while now.

[94_240sx]

Rear GTR stock sway is 26mm.

Found that HICAS rear swaybar is 21mm. GTR stock is thicker. I've been thinking about whiteline swaybars because they are adjustable, but seems like naed is not happy with them. I wonder if they will better with SPL end links.

[Hijacker]

currently still using a spring/damper combo with tein s techs and AGXes. eventually I'll be upgrading to some coilovers, but for now the teins and agxes work good for auto-x.

[94_240sx]

currently still using a spring/damper combo with tein s techs and AGXes. eventually I'll be upgrading to some coilovers, but for now the teins and agxes work good for auto-x.

Got it. I asked because with coilovers you might be able to reduce understeer by adjusting dampenings.

I wonder about this. There are some thick rear sway bars out there like Largus, Godspeed and Tanabe. ST is only 21mm BTW. On the other hand, whiteline is 22mm. If I set whiteline sway bars in full stiff mode, it'll work as good as thicker sway bars? If so, I'd go for whiteline.

[DukeBoy]

Have you tried removing your front sway bar. It tends to reduce understeer if you remove it. Mine is gone. I still have the stock rear sway bar though. Try it and see how you like it. It's cheap and easy to do. The only other thing would be a roll bar or some type of rear brace to keep the body from twisting. Even with my silkroad coilovers, the vert still had an enourmous amount of roll and understeer that only the roll bar corrected. The body was twisting so much that the muffler was dragging while drifting right. Let us know what you decide.

[onosqv]

I can't really tell you exactly how much difference just adding the rear sway bar does bcs I added mine w/ my coilovers.

Adding the swaybars at the very minimal helped since my bushings were cracked to hell on my coupe. I personally run the Suspension Technique ones. I'll be moving those from my coupe -> vert soon, but probably also several different pieces. I have coilovers too, and those will solve basically all your understeer problems. I can adjust just a few clicks during a practice session and get the car to understeer, oversteer, or be basically neutral.

With my vert @ the autox, I've been able to fix some of the understeer by lowering tire pressure in the front tire & raising tire pressure in the rear. I'm currently running stock suspension staggered on 215/45R17 or something & 235/40R17 or so in the back, which isn't helping much w/ the understeer considering the rear tire is also more grippy .

My friend has apex'i coilovers + tanabe swaybars and loves it. Basically no understeer during the last autox we went to.

Sorry I can't give you a comparison of just rear swaybar, hope the info helped somewhat.

In any case, imho, you should always upgrade both front & rear bar from the company you choose. Sway bar manufacturers, such as Largus, design their swaybars to work with each other. So if you just add the rear, you may start getting very weird response handling.

You can also get the bars from FRSport :

Largus Front & Rear Swaybar for S13

Tanabe Swaybars for S13

[onosqv]

And to throw in a little more possibility other than sway bars... what are you alignment settings? those usually help out a lot with handling characteristics. After a year of tweaking around w/ different alignments, I found the "miata autox" alignment (slightly tweaked for my taste of course) worked out best for me... i.e. slight toe out front, slight toe in rear. lots of camber. lots of positive caster up front.

And to make matters even crazier... I want to bring up a post by a solo2 veteran from our local autox board regarding adding swaybars on fords and understeering, talking about front swaybar bcs of the class restriction of the subject (www.solo2.com):

Other than that, camber and caster to the max of rules and the car, is the best way to go... You may find that a massive front sway bar will actually make it better... Odd? Not so much... The stiff as hell front bars stop the front end geometry from, well... changing... this sort of "locks" the geometry in place. this reduces positive camber gain mid-turn and therefore allows the tire to work better.