Originally posted by AirKnight:
Originally posted by Munch:
If I did the numbers right, a 24mm hollow bar would have to have a 9.5mm (~3/8") wall thickness in order to have the same torsional rigidity as a 22mm solid bar, assuming the same material (i.e. shear modulus) in both bars. But, with the hollow bar, you'd save about 2 lbs. for every foot of bar length (if it's made of say, steel). Assuming the bar is say 4 ft long, that's 8lbs. of weight savings using the hollow bar. Hey, every bit counts!



Damn you two for making me think about my Mechanic of Solids class the last week of break! DAMN YOU TWO!

Now, why does torsional rigidity really matters that much??? I thought it's the lateral forces are the ones that the sway bar are there to prevent? I mean, the sway bars are there to reduce chassis flex when cornering, so it's compressed left to right? So shouldn't you be more worried about the direct shear and stress?



Not lateral forces, but lateral weight transfer of the car via vertical deflection of the suspension, which is resisted via the torsion of the swaybar, per Demon.

Function before fashion. '96 Contour SE "Toss the Contour into a corner, and it's as easy to catch as a softball thrown by a preschooler." -Edmunds, 1998