Anti Roll Bar Tech Question

[EB2019]

Hi

Forgive me if I'm wrong about this, but I’m trying to understand why the difference between these two ARB applications/designs.

Aftermarket ARB's have bushes that allow the bar to rotate or twist freely? For example if you get an even compression across the axle path, the bar gives no load to the suspension and doesn't change spring rate, it only applies load when you have an independent wheel moving to compress or extend (cornering). This seems to me what a ARB should be like, no spring rate change unless you are cornering or going over uneven bumps.

The OE bars appear to me to have the bushes bonded (without end links attached it doens't move). Because of the lack of movement it appears 'almost' to restrict the bar from rotating when even compression across the axle is applied or when cornering.  This restriction appears to act like a torsion bar more than a free moving ARB? I would have thought that this would ramp up spring rate significantly as the wheel or wheels compress into the suspension?

Any thoughts why these 2 are so different, and what is going on with the bushes on the genuine bar?

Please feel free to ignore this but these things bug me when I don't understand the reason behind something. 

 

[madstaff]

I think your right in saying with the bonded bushes the roll bar can still flex, but the bar becomes an additional type of torsion resistance to suspension travel as it requires force to distort/deform the bushings.

[EB2019]

If that is the case, what would be the difference to replacing the bushes with Powerflex and allowing the bar to rotate freely?  This should improve the independence of the rear axle as the movement of one wheel doesn't have to overcome the torsion effect? but still offer the same anti roll bar stiffness (all other things being equal).

Perhaps why aftermarket bars are much thicker/stiffer so to still ramp up spring rate even above the oem likely spring rate?

Likely I'm just over thinking it, and quickly heading down a rabbit hole of internet searches about spring rates lol