How stiff if stiff enough. Weight V's Stiffness.

[ottocycle]

Hello all,

I am new to the site and would like to start a discussion that might help me understand things better. We all know that chassis stiffness is critical for good handling and chassis tunability. What I have never heard discussed is chassis stiffness versus car weight. In other words will a 3,000 lb. car have the same dynamics as a 1,500 lb. car assuming they both have a ridgity of 3,000 ft. lbs. degree (all other things being equal as much as possible)? Also as we try to minimize weight as much as possible it seems to me that the influence of unsprung weight to sprung becomes more important. What is the impact of this? I have been a fan of lightweight cars for years and while not an engineer I would love to learn more on the subject. If anybody knows of a source of further information that is not too math heavy I would love to hear about it. It would be interesting to hear of rigidity figures quoted as a multiple of vehicle weight.

I hope I am making myself clear.

 

Cheers,

 

Dermot.