By using split-rate shocks between pairs on each end of the car, we cantighten the car on entry to the corner. If the RF shock is stiffer incompression than the LF, and/or the RR shock is stiffer in rebound, thenthe crossweight percent (RF + LR combined weights) will increasemomentarily while the suspension is moving and adjusting to the transferof weight due to deceleration.
The term "tie down" is often used to refer to a shock that has a high resistance to rebound. If the rebound rates are higher for both left side shocks than those of the right side shocks, then as the car turns left (especially with quicker turning rates associated with smaller radius turns), the tendency for the left side suspensions to quickly rebound as weight is transferred from the left side to the right side is reduced.
If we can stop the sudden motion, we can keep the left side down on initial turn in and the chances are good that the whole attitude of the car through the middle of the turns will be lower. A lower center of gravity (CG) means less weight transfer off the left side of the car and more retained left side weight. For asphalt stock cars and dirt cars on higher-banked tracks with grip, a higher left- side weight means more equally loaded tires, left to right, and more traction. The opposite is true of dirt cars on slick tracks.
The reverse term, or "Easy Up" shocks, are used to help raise the suspension quickly which does also raise the center of gravity of the sprung mass and a higher CG promotes more weight transfer. Drag cars use this effect on the front of their cars to promote more weight transfer to the rear tires for added traction. On dry, slick dirt tracks, teams can utilize less rebound in the left side shocks and in the front shocks to promote weight transfer to the right side for better side bite and to the rear for better traction off the corners.
By using split-rate shocks between pairs on each end of the car, we cantighten the car on exit off the corners. If the LF shock is stiffer inrebound than the RF, and/or the LR shock is stiffer in compression thanthe RR shock, then the crossweight percent (RF + LR combined weights)will increase momentarily while the suspension is moving and adjustingto the transfer of weight due to acceleration.
Putting All Of This to Use
In order to utilize the configurations we have discussed here, we must be able to use a range of different rates of shocks in order to find the right combination for our car at a particular race track. For a team that races at only one track, the process is fairly simple. You would experiment to find the fastest set of shocks and ones that suit the driver's style and stick to those. For teams that travel to different tracks, some changes will be necessary if the setup needs to change and/or the track layout is different from track to track.
Many shock experts agree with certain basics, such as:
1. The shock package should be softer overall when racing on dirt and when the track is flatter when on asphalt.
2. Get your basic setup close to being balanced before trying to tune with shocks. Shocks cannot solve basic handling balance problems.
3. Higher-banked tracks require a higher overall rate of shock as opposed to flat tracks. This is because of the higher speeds and the extreme amount of downforce.