Drilling an extra hole in a sway bar end to give a softer setting

[steved0x]

Crazy talk? Looks like there is room on the flat part before the bar resumes the tubular part.

[Edit: Now I understand that if I were to drill a hole like I describe it would yield a harder setting...]



I removed this and replaced with an Eibach adjustable 22 mm tubular bar with three holes on each end, but was looking at this one (19 mm) now that it is removed.

Seems like a 22mm bar would be more stiff then the OEM 19 mm bar, it was quite a bit heavier? I don't know the wall thickness so don't know how to compute stiffness.

Does anyone know how the 22mm Eibach will compare to the 19mm M030 S rear bar. The middle setting on the eibach lines up with the holes on the OEM bar.



I figure having some adjustment capability may be good to help me get dialed in.

[ianacole]

My understanding is that moving the attachment point in toward the bar part makes it stiffer... the closer you get to the bar itself, and thereby the mounting point, the less flex you get.

[steved0x]

I thought it was the opposite, moving inward shortened the lever arm and therefore exerted less force over on the other side... I better go look it up before I go to adjust the bar and have the opposite effect

I see what you are saying? Longer arms gives more twist and therefore exhibits less force over to the other side?

Hmmm... More research needed....

[boxxster]

Think of trying to snap a pencil in half. More force is required to break it the closer together you move your hands. Same with the sway bar. More force is required to contort it as you move the mounting location inwards so it functions as a stiffer bar. You can actually have different settings on each side of the bar if you fine you need to fine tune the stiffness more precisely.

[steved0x]

I see.... Not really but I will let it roll around in my head. At least I know which way to adjust the drop links now

[ianacole]

It's a torque measurement ... where your bar mounts to the frame is your pivot point or fulcrum. The amount of force it takes to have the same about of torque lessens the further out from the fulcrum you move.

T=F*D (Torque=Force X Distance from Fulcrum)

100 t = 100ft/lbs x 1 ft. or
100 t = 50ft/lbs x 2 ft.

A bit of an extreme example since a sway bar is ~ 1" difference from the two most extreme settings, but it show the further you move from the fulcrum the less force it takes to achieve the same torque.

[thstone]

Simple - the longer the lever, the less force required to create the same torque.

With that being said, here is a chart with stiffness comparisons for Porsche bars and the adj Tarett bars - unfortunately haven't seen data on the Eibach bar;

[geetee]

you can always tighten up the front more

[steved0x]

Originally Posted by thstone

Simple - the longer the lever, the less force required to create the same torque.

With that being said, here is a chart with stiffness comparisons for Porsche bars and the adj Tarett bars - unfortunately haven't seen data on the Eibach bar;

I got the specs from Eibach on their rear bar, 22mm diameter 4.76mm wall thickness.

Originally Posted by Tanner from Eibach

Hello,

The wall thickness is 4.76MM on this bar.

If you have any other questions please feel free to respond to this email.

Tanner Hallihan | Direct Sales

Eibach Inc. | 264 Mariah Circle | Corona, CA 92879-1751

That bar is stiffer than OEM, and it works out like this, in comparison to the OEM Base/S rear bar, similar to the chart above:

Hole 1 (stiffest), 2.78
Hole 2 (same as OEM), 2.5
Hole 3 (softest) 2.22

The front bar that goes with it (that I don't have) is a 26mm solid bar.

It is 2.134 times stiffer than the Std Base front bar.

So if you're looking for some stiff swaybars, these are it

I am back to OEM M030 S for now while I tune some different parts of my suspension.

Steve

PS I got the formulas and things to make these calculations from this thread: https://forums.probetalk.com/showthread.php?t=1701130839

As a sanity check I plugged in all the numbers from the Tarett spreadsheet using my formulas and they matched