Swaybar info please...

[greg V]

I am building a tube frame 'tin top' race car and need to design in a swaybar. Being I am using pushrod suspension and where everything is placed, the below setup will work perfect for me. But, I have never built one like it, so I have a couple questions that I hope can be answered here.
First, the blades. These seem to be specialty made and not the typical adjustable ones for sale, like Genisis. Correct? If so is there somewhere I can find them? I can just buy some and modify them, but....
Material? Is the "twist" taken up in the longitude bar or just in the blades? What material is being used? I'm thinking that I am seeing maybe 3/4" to 7/8" DOM, with maybe a .120 wall?

Thanks
Greg

[RobLav]

These can get very highly stressed (and expensive). The "twist" is taken up by both the bar and the tube. Usually made of heat treatable steel then heat treated (like 4130 or 4340). If you are starting from scratch with a heavier tin top, you ought to conduct some calculations to determine the ballpark area of the size required. I'm also in NE CT (Scotland) so feel free to stop by.

It is an anti-roll device - anti-sway or swaybar is a bad term.

[greg V]

PMed you Rob. I couldn't be much closer.

[racedata]

I am building a tube frame 'tin top' race car and need to design in a swaybar. Being I am using pushrod suspension and where everything is placed, the below setup will work perfect for me. But, I have never built one like it, so I have a couple questions that I hope can be answered here.
First, the blades. These seem to be specialty made and not the typical adjustable ones for sale, like Genisis. Correct? If so is there somewhere I can find them? I can just buy some and modify them, but....
Material? Is the "twist" taken up in the longitude bar or just in the blades? What material is being used? I'm thinking that I am seeing maybe 3/4" to 7/8" DOM, with maybe a .120 wall?

Thanks
Greg

It seems that on the design you posted, the tubes take no load in bending ? ie, in roll the left side goes down and the other one goes up ? In heave the (both wheel compressing) the hiigher part of the ''T'' seems to be mounted on bearings ?

That being said, the lower part of the ''T'' would need to have a high resistance in ''twist'' for basic calculations of a round bar in torsion you can look up Wikipedia, basically the higher the outside diameter you have, the thinner the wall can be to have the same stiffness in torsion.

For material, you need something that has a good life in fatigue (no aluminium here haha) and a part that has the required stiffness AND that is not too brittle as it will be bending and unbending several times in a lap.

Also, ideally you want to be able to adjust the roll stiffness within a range that will give you good ajustability for different tracks, conditions and drivers