Increasing Rear Sway Bar diameter

[Shrike]

What are the effects of oversizing a rear sway bar? Also, would underlubricated swaybar chassis bushings effect the suspension geometry, especially when encountering road bumps and dips. Please consider that the vehicle's chassis and suspension are extremely stiff, with bound/rebound adjustable shocks and a low riding vehicle.

Thanks,

Dave

 

[Fabrico]

That depends on how low and stiff things really are. If the description is accurate, it may do nothing.

 

[GregLocock]

If the sway bar to body bushes are seized when they should be freely rotating then the sway bar will act as a spring in bump, via the torsional rate of the sway bar bush. It will also increase the roll stiffness of the rear.

Increasing sway bar diameter will increase the weight transfer at the rear and will generally reduce linear range understeer, and reduce traction out of the corner and under braking for that axle.

In a well set up RWD car it is probably the least useful/most harmful simple modification one can make, other than raising the CG.

Cheers

Greg Locock

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[patprimmer]

Like Greg said

In addition, bushings will not effect the geometry as such. The same suspension travel will result in the same wheel position and orientation, but the spring and/or roll rate will change and as a consequence suspension travel will change as will individual wheel loads during movement.

Regards

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[NormPeterson]

I suspect that increasing the amount of rear bar relative to the amount of rear spring will make the inside rear wheel slightly "lazier" in following the back side contour of a pavement bump encountered while cornering.

If by "underlubricated swaybar chassis bushings" it is meant that the bar in question still rotates within said bushings, then they would also be introducing some smallish amount of damping via friction (and likely a few squeaks as well).


Norm