This is the ratio of applied torque and angle of deformation, where F is the force caused by the applied mass and L is the length from the point of the force to the point of rotation. The value of torsional stiffness is useless unless it is not compared, usually com-pared with the roll stiffness of the suspension. As the vehicle has two axles and each can have a different roll stiffness, influence by linear and nonlinear suspension system.

refer this paper:

https://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=2883&context=theses

Thanks Mahmoud.

The torsional stiffness of a car refers to its resistance to twisting forces. It is a measure of the amount of energy required to twist or rotate a component. Factors influencing torsional stiffness include the material properties of the component, its geometry, and other structural elements. The torsional stiffness of a component is typically measured in Newton-meters per radian (N/rad).

I would use torsional resonate frequency.

The torsional stiffness of a particular vehicle can be compared directly with the stiffness of other vehicles of the same category. Another possibility is to determine the torsional stiffness gradient, i.e. along the length of the car.

Marek Maciejewski 1. When you talk about the same category are you talking about segment A, B, C, D... ? (Euro Car Segment). 2. What do you mean by stiffness gradient ? The lightweight rating number ?

Do you have some formulas ?

Thank you

Any type of hole in the chassis/sub-frame, pillars, etc- is a reference for where torsion will change from the reductive formulation into discrete differentials.

+1 for torsional resonance frequency.