Stillen Sway Bar Charts

Trilitheum

Thought I would put these up for anyone else who is interested. I recently purchased the Stillen sway bar kit and was trying to understand how much adjustability was possible between the two bars.

The charts show all the possibilities between the two bars and the relative changes from OEM that can be set with the bars.

What I was trying to determine was how much the balance of the car could be changed. Obviously the higher the % stiffer than stock the less roll, but I was more interested in how it would change the over/understeer tendency, which depends more on the ratio of front to back, not the absolute values.

Due to a host of variables, the percentages and numbers won't directly translate in X percentage increase in over or understeer on the car but it gives an idea.

Stock OEM ratio of front/rear is ~1.04 (Green), so for example anyone interested in keeping the same car balance on these bars but want less roll the settings would be 4 in the front and 1 in the rear.

From reading other threads it appears that with the stock suspension, a close to neutral balance is around a setting of 3 on the front and 2 on the back (ratio of 0.87), so this can be used as reference point for adjusting either way on a otherwise stock car. If you modified your suspension, tire size, spacers, etc. these guidelines don't apply!


*Charts are for information only, accuracy is not guaranteed

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

Jordo!

Very useful for those who have these -- nice!

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Enjoy it. Destroy it.

Trilitheum

Here are the calculations I ran for the Eibach bars as well. There is a lot more room to adjust the car into understeer but less margin to move into oversteer.

For the Stillen bars I would call them oversteer biased, for lack of a better term, and the Eibach's are about equal biased to dial in over and understeer. Both have 15 possible settings.

It should be noted the stiffness % over stock is much higher on the Eibach kit compared to the stillen bars, so the response and ride will be different.


*Charts are for information only, accuracy is not guaranteed

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

Fishey

This makes absolutely no sense to me.

How do you get 5 settings on just the front bar if it has 3 holes? or 3 settings on the rear if it has 2 holes?

I see the way you labeled it but that is going to cause some serious handling issues. The leverage point is always between the closest body mount and the swaybar endlink. The far endlink will not offset the geometry change because of different torsional loss over the length of the bar. I would never run an offset swaybar setup unless I was doing it to achieve a certain goal like maybe circle track racing.

DR_

The bar has two lever points since it has two mounts to the car, which makes the whole bar one spring rate, not two like you are proposing. People mix the sway bar settings all the time with no ill handling. I believe he got that first picture of the 5 way setting straight from Stillen so the manufacturer endorses doing this.

Trilitheum

^^My understanding is that with a two point mounted bar you can stagger holes with no problems at all.

I know for sure that Stillen does endorse and support this for their bars.

Stillen Front Sway bars, now adjustable

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

ZMan8

nice info

Can you get this info for whiteline sway bars as well?

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

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2010 370Z 40 Anniv., 6 MT | Fast Intentions | Swift Springs | SPC | Z1Motorsports | JWM | Redline Oils | 35% Window Tint
2015 Mazda6 | 370ZChicago: Chicago Area Cars & Coffee

Trilitheum

Yes, I am looking for accurate spring rates for the Whiteline bars to run the calculations.

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

DR_

Did you see this?

Trilitheum

Yes! it has great info on the torsional stiffness of the bars. It doesn't have all the data for the various spring rates for the different hole positions on the Whitelines (and a few others).

I do have the chart from Whiteline showing the % Stiffness over stock, I just back calculated the lb/in spring rate, I am putting together the table right now, should have it up in a few minutes...

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

Fishey

That is not how physics work.

So to make this point I made a simple representation that I think we can all understand. You can thank my Nephew for having some sweet toys to help this make more sense.

Uneven spring rate will be the result if you run uneven holes.

Consider this photo to be the far hole in the swaybar being loaded with the longer leverage arm.



Now, consider this to be the close hole loaded and the shorter leverage arm.



Notice they are not equal? Because effective resistance is not equal across the bar. I hope this helps to convince you that handling will be different left to right.

-Your Pal
Fishey

dastaco

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Trilitheum

Ok, if you search the web for using different settings on sway bar ends you will find people arguing to no end if it does cause asymmetric loading, and if it does is the absolute force difference enough notice.

There doesn't seem to be a lot of consensus. If the bar is acting as a torsional spring, or a "passive through member" in relation to the chassis roll and if the twist angle of the bar is constant along the length or not, etc.

I honestly don't know which is correct now, as there is so much conflicting information.

With respect to these tables, the values will be correct, but it is uncertain if the staggered settings (Position 2,4 on the 3 hole, Position 2 on the 2 hole) will cause some sort of asymmetric loading. If you believe they do, do not use these settings, the rest are still valid.

^^Very cool toys your nephew has, I agree this shows the difference in moment arm length, but you would have to measure the force being applied to the white end piece resting on the table to show the load was asymmetrical, and both ends would have to be allowed to move freely.

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

Trilitheum

Here are the tables for the Whiteline Sway Bars.

* Charts are for information only, accuracy is not guaranteed

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2011 Nissan 370Z Touring/Sport, 6MT, KAD

ZMan8

If im reading this correctly whiteline bars are not as good at inducing oversteer. Nor are they as stiff as I thought they would be.

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

__________________
2010 370Z 40 Anniv., 6 MT | Fast Intentions | Swift Springs | SPC | Z1Motorsports | JWM | Redline Oils | 35% Window Tint
2015 Mazda6 | 370ZChicago: Chicago Area Cars & Coffee