I copied this con buddyclubuk.com, I've had these fitted for a few years now and have never had any issues
WHAT IS ROLL CENTER ?
While a vehicle corners, the movement of suspension is focused on the intersection (instant center) of the lines extended from the upper and lower suspension arms.
The intersection between the line from where the wheel contacts the road to the instant center (Point P) and the vehicle body centerline is the roll center (Point B).
With the stock suspension, the appropriate roll center has already been set from the factory.
ROLL INCREASES AFTER LOWERING?
Simply lowering the car results in an increase in the distance between the center of mass (Point A) and roll center (Point B) of the vehicle, even though the center of mass has dropped.
When the distance between Point A and B increases, roll stiffness decreases, causing an increase in the amount of roll. The amount of roll can be controlled with the use of stiffer springs, but ride quality etc. suffers as a result. Cornering speed does not increase like originally thought.
ROLL CENTER ADJUSTED!
With the Roll Center Adjuster in place, the angle of the lower are is revised. Roll center (Point B) is once again close to the center of mass (Point A) of the vehicle.
With the lowered center of mass and increased roll stiffness, the limit of cornering speed increases.
ROLL CENTER ADJUSTER FF
When a FF vehicle is lowered, the angle of the lower arm becomes poor, resulting in a significantly lowered roll center.
Consequently, the amount of roll in corners increase and the cornering force is sacrificed.,br> By extending the ball joint of the front knuckle, the position of the roll center is altered. Replacing the stock ball joint with this product will result in reduced roll, and cornering force as a result is increased. Steering response is also improved. This product is the long-awaited part for FF vehicles.
