1st off- Coilovers in the FRONT of a G-body, that use the stock mounting locations are a HORRIBLE choice!! They do not allow for enough stored energy in the springs for efficient weight transfer.
Because the coilover in the
front in
stock mounting locations have such a shorter spring, it means that the spring rate must be stiffer, which means that when at ride height the spring is barely compressed. The amount a spring is compressed is the amount of stored energy in the spring (relative to the spring rate) that is available at launch for weight transfer.
Smaller/shorter spring with a very high spring rate = barely compressed spring, which means there is very little energy in the spring to help you hook up at launch.
Back to your question...
If you are looking to lower the car in the front, the absolute best pieces you could put on your car would be the SC&C/SPC double adjustable upper control arms with the Howe extra tall ball joints, and the SC&C/SPC lower control arms with the modular spring pockets.. OR The SC&C/ATS ATX spindle system.
Here is what the SC&C double adjustable UCA's and the SC&C LCAs look like installed on a car with the Howe Extra tall ball joints:
The SC&C/SPC upper and lower control arm system is the only system that fundamentally addresses the geometry issues of the G-body by fixing the front pickup points of the tie rods and LCA ball joint locations on the spindle, which are the direct cause of the bumpsteer issues on our cars. It should be noted that just by swapping to this system will drop the car between 1"-1.25" but with the modular spring pocket the SPC LCA's have, you can raise the ride height of the car up to 2" through the usage of spring shims.
This system was the original system to use the larger ball joints, which you see every other company copying today. The SPC lower control arms use a modular spring pocket that allow you to run either shocks or coilovers, and also allows you to adjust the ride height of the car up to 2" by using varying thickness spring inserts. Start with a shorter than stock spring, maybe 2" short than stock but same spring rate. If the car sits too low, use any combination of the spacers that come in the kit, and place them under the spring pocket to raise the ride height of the car without having to swap new springs.
Here is a picture of my dirty SPC lower control arms and the modular spring pocket at the bottom of the spring. It is the grey piece underneath the black spring, that you can see is in a circular shape around my Varishock QS2 shocks:
Another pic of my dirtyass arms showing the spring pocket:
FOR REFERENCE, What the control arms look like without the spring, shock, or modular spring pocket installed:
In the rear I would suggest running a shorter spring but with a set of shocks that have a very wide range of adjustment. My personal favorite are Varishock QS2 double adjustable shocks. They are true pro-touring shocks that work well for both road racing/auto-x and for the drag strip. They have that broad of an adjustment range.
Nothing can come close to the performance of the SPC setup for the front of the car for geometry correction, and performance.
If you want to lower the rear of the car, get yourself some GOOD shocks, and pick up some springs with the same spring rate but maybe .5-.75" shorter if you are looking for a 1" drop.
Hope this helps!
