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Message: <blockquote data-quote="willy5" data-source="post: 692153" data-attributes="member: 2319">Cocky! Reducing body roll works up to a point, see last paragraph, this is taken from the web, there are many other sources too[h=2]Roll Resistance[/h]Anti-roll bars are used to reduce body roll during cornering. They add to the roll resistance of the suspension springs for a higher overall roll resistance Because the primary purpose of the spring is to maintain maximum contact with the road surface over imperfections, we must settle for the roll resistance provided, and it is rarely enough. The anti-roll bar adds to the roll resistance without resorting to an overly stiff spring. A properly selected anti-roll bar will reduce body roll in corners for improved cornering traction, but will not increase the harshness of the ride, or reduce the effectiveness of the tire to maintain good road surface contact.So, how does limiting body roll improve handling? The suspension system geometry (the lengths and connecting points of its parts) of a street car is designed to keep the bottom of the tire parallel with the road for maximum contact patch. At rest, the car's suspension has a particular geometric relationship to the road surface. Body roll changes that relationship, and reduces the suspension's ability to keep the tire parallel to the road.During body roll, the car body is no longer parallel with the road, and neither is the suspension geometry. Even though the suspension allows the wheel to be somewhat independent from the body, the high cornering forces, and resulting large body roll of a factory car, on the track take the suspension close to its limits where it affects the angle of the wheel.Large amounts of body roll cause the wheels to tilt away from the corner which lifts the edges of the tire and reduces the contact patch size. While this can be compensated for by having the wheel purposely tilted inward to start (adding negative camber), there is a practical limit to this which is not enough in most cars to compensate entirely for the body roll. The anti-roll bar reduces the amount of body roll, and therefore helps to maintain as much of the contact patch as possible.As with all good things, more is better only to a point. Because the anti-roll bar connects the left and right sides, this reduces the independence of independent suspension. Too stiff a bar, and you can cause too much loss in the ability of the left or the right wheel to independently respond to road surface imperfections. The purpose of suspension is to maintain maximum tire contact with the road. The purpose of independent suspension is to allow the left and right wheels to each seek that contact separately. The left wheel may need to be going down when the right needs to be going up. If they were tied together as with the old floating rear axles, one or both of the wheels is not achieving maximum contact. In fact, too stiff an anti-roll bar can actually cause an inside wheel to lift completely off the ground during hard cornering.</blockquote>

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