The question no-one was asking

What he said.
Results ranged from 8,800 to 9,650 lb ft/degree. We think that’s about 2.5x the original value, currently looking for actual data.

The torsional stiffness value was traditionally considered an important measure of the car’s ability to maintain suspension geometry under cornering conditions. As most cars developed that to reasonable levels the focus shifted to expressing it as a frequency - the frequency the structure would freely vibrate at after hitting a bump. A higher value gives a better quality ride feel (less shakes) and more headroom for suspension tuning as the dampers, tyres & bushings can be selected or set to control the major up-down motion body on road swells, with less interference from shaky feel over rough surfaces.

The frequency calculation takes the weight of the car into account so gives a more realistic comparison of a large vs. small car than a basic stiffness value.
I’ll do that, but it’s a bit early in the day to be dealing with square roots.

(Was that schmancy enough, Paul? I have more)

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