Designing the structure this way also allows us to use the rear crossmember to mount the rear coilovers to the chassis. This is a very strong point for the weight of the car to be supported. We now have a one-piece weld-in structure that the suspension mounts to. The beauty of this system is there is minimal altering to the car. The factory sheetmetal crossmember needs to be cut out, a little paint needs to be ground off for welding, and the four mounting points need to be welded on the inside of the framerails-that is the extent of the alterations to the car.
We wanted the car to work well on the dragstrip and have great road manners, and it does. The car seems to be smooth under launching and acceleration. There is no snap or wind up of the suspension during launch. It has a firm positive feel on the road. In addition to the many benefits this system has over the stock leaf-spring suspension, the entire system is also 50 pounds lighter than the stock-style suspension using super-stock leaf springs.
Now that everything is disassembled,...
Now that everything is disassembled, the factory rear shock crossmember needs to be removed. It can be cut out with a cut-off wheel. After the rear shock crossmember is cut out, the framerails need to be ground smooth so there is room for the new crossmember to be cleanly installed.
This is what the new rear...
This is what the new rear suspension pieces look like. The kit includes many cool pieces, such as fully adjustable upper and lower four-link bars and really trick QA1 12-way adjustable shocks and coil springs.
Now that the framerails have...
Now that the framerails have been ground smooth, the new tubular rear crossmember needs to be located and welded in place.
The lower four-link bars are...
The lower four-link bars are now ready to be installed on the car. Before this can happen, they need to be assembled. There is a bracket included in the kit. This mounts in place of the factory front spring-hanger. This bracket provides the mounting point where the lower link-bars attach to the chassis of the car. Note: It is a good idea to adjust both of the lower four-link bars to exactly the same length before the bars and brackets are assembled. This will help ensure that the suspension will go together keeping the car square.
Both of the upper link bars...
Both of the upper link bars can now be attached to the crossmember. These should also be matched in length like the lowers were.
The rear axle needs to be...
The rear axle needs to be supported and carefully positioned underneath the car exactly where the ride height will be. At this point, the weld-on tabs can be attached to the upper link bars. The weld-on tab and upper link bar assembly can now be lowered down on the axle tube to locate where the tabs need to be located. After positioning the tabs and spot-welding them, we removed the rearend and finished welding the tabs to the housing. Note: To be safe, we recommend removing the center section and axles so you can clean the axle tubes after welding.
The brackets that attach the...
The brackets that attach the lower link bars to the axle now need to be assembled. The first step is to bolt the aluminum lower shock attachments onto the brackets.
Now the shocks can be bolted...
Now the shocks can be bolted to the crossmember, and the rear axle can be rolled back under the car for installation.
With the rear axle supported...
With the rear axle supported under the car, the upper four-link bars can be bolted to the rear axle.
The bracket assemblies can...
The bracket assemblies can now be held up to the axle and the U-bolts dropped in. You will probably need a third hand to hold this together while the nuts are put on and tightened.
The shocks can now be bolted...
The shocks can now be bolted to the axle. Now that the shocks are attached, the support holding the axle up can be removed. At this point, the brake lines and the driveshaft can be reinstalled.
Now it's time to attach the...
Now it's time to attach the bracket assemblies that attach the lower bars to the rear axle. This bracket assembly is bolted on the axle using three U-bolts per side. Because of the length of the bracket, a second spring perch is used to support the bracket. It is not necessary to weld this perch to the axle because the original perch is used to locate everything. You can, but the second perch is only for support.
Now that the system is installed,...
Now that the system is installed, there are a couple adjustments that may need to be made. Shortening or lengthening the lower four-link bars will alter the wheelbase of the car by moving the axle forward or back. If the car is out of square, one lower bar or the other may need to be adjusted to slightly alter the position of the axle in the car. The upper four-link bars can be shortened or lengthened. By doing this, it tips the axle up or down, making the pinion angle adjustable.
With everything back together,...
With everything back together, it's time to set the car on its tires and make sure everything is square. At this time, we took the car for a couple of slow trips up and down the driveway, just to see if it tracks straight. If not, adjust the bars until it does.
Once you're sure everything...
Once you're sure everything is square and tight, launch it.