Now it should be stated here what sway bars essentially do, even though I know you may already know this. What a sway bar does is counteract the action of body roll during cornering by transferring spring rate from the inside wheel to the outside wheel in a corner. This means that you don't actually get any added spring rate; you just subtract it from one side and add it to the other. This has the ultimate effect of transferring load from the inside tire to the outside, which has the visual effect of compressing the suspension on the inside of the turn and expanding the suspension on the outside of the turn (thus limiting body roll). This is good mainly because it smoothes the speed of weight transfer during quick transitions and also limits the camber change experienced at the corners of the car through suspension travel. And of course, using this concept one can dial in the amount of total loading on the outside tire by varying the effectiveness of the sway bar (stiffer bars equal more transfer). And the beauty of all this is that it mostly only occurs during cornering, so our straight line spring rates are not affected. The other thing Ok, so hopefully now you all understand this concept. This is the most important part though, so if anything is still fuzzy read this again until you get it. Also, here's an example of how this works:
-For this example we will use a sway bar with a roll stiffness of 250 lbs.
Left front static load: 1000lbs
Right front static load: 1000lbs
-lateral weight transfer in a right hand turn
Left front: + 500lbs
Right front: - 500lbs
Total weight transfer: 1000lbs
-load transfer of sway bar(which is 250 lbs):
Left front: +250lbs
Right front: -250lbs
Total weight transfer: 1000lbs
-total effective cornering load for this example:
Left front: 1000 + 750= 1750lbs
Right front: 1000 - 750= 250lbs
-without sway bar
Left front: 1000 + 500= 1500lbs
Right front: 1000 - 500= 500lbs
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Gaetano Cosentino
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