As far as geometry related to rear steer is concerned, this is an ideal system for asphalt cars. The amount of rear steer due to body roll is regulated by the height of the front mounts of the arms, which are always mounted lower than the rear point of rotation which is the axle. Rear steer amounts due to the Panhard bar angle are regulated by the angle.
The Metric Four-Link SystemThe metric four-link is widely used for the stock classes where the host car's design utilizes that system. It uses four links, as the name implies, that aren't parallel to the centerline of the car. The top links are angled from a top view with the front pivots wider than the rear pivots. The lower links are angled from a top view with the front pivots narrower than the rear pivots.
Conclusion On asphalt, we don't want to make large changes to components that influence rear steer. Make small adjustments if you feel you need to, and when you find the correct amount of rear steer, stay there and tune the handling with the other components. Drivers can feel small changes in the height of the front mount on a right-side trailing arm.
The pullbar upper third link...
The pullbar upper third link allows the rearend to rotate under acceleration. The movement of the rearend rearward can be utilized to produce rear steer to the left only while under acceleration. That way, the car is correctly aligned at the rear during entry and through the middle of the turns. Rear steer to the left helps promote bite on flat and slick asphalt tracks. Rob Fisher
Some three-link rear suspensions...
Some three-link rear suspensions are built with the trailing arms angled from a top view with the front mounts located closer to the car's centerline than the rear mounts. This creates some amount of rear steer if the rearend moves laterally as the chassis rolls. This type of rear steer will tighten the car if the rearend moves to the right as the car rolls. The downside to this type of rear steer is that it will tighten the car in the middle of the turns as well as off the corner.
The metric four-link suspension...
The metric four-link suspension has two links above the rearend and two links below the rearend. They are angled from a top view to prevent the rearend from moving side to side as the chassis rolls. This system would work very well with larger sway bars. The high rear roll center works in conjunction with a stiff front end to reduce roll in the chassis.