Originally Posted by TheDirtman

With a light 2 door I would go with a lighter coil set up. Maybe 100 over 200 and you may need to run a shorter upper coil. When you can, measure what you have as far as shock length at ride height (eye to eye) and then jack the jeep up until the weight is off the coils. With this and your current spring rates you can figure your sprung weight and size the coils you need. Example if you have 200/250 coils your rate is 225 pounds per inch, if your shocks compress 3" at ride height you have 675 pounds of sprung weight on that corner. With 100/200 upper effective coil rate is 150 per inch and 675/150=4.5" of compression. This would give you a ride height 1.5" lower then you have now but you still have no preload on the coils. When tuning with King they start with 1.5" of preload on the coils and tune from there. The upper and lower coils do not have to be mounted in that position so you could run a 200 lb upper in the lower position, just make sure it is as long as the travel on your shocks or the slider will leave the shock body and get hung up on the shaft. The white numbers on the coils will list the diameter, length, and coil rate. I find that the EVO set up is a bit on the heavy side and is set up for a heavy JKU. The lower your coil rate is the more comfortable your ride should be up to a point, you don't want it so soft that you are bottoming out under a relatively mild trail, say going 40 mph on a rutted road. You will get more body roll from softer coils so if you drive your jeep like a race car you may want to have the heavier coil rate. Of course the shock valving will have an effect on theses ride characteristics. Also what is your nitrogen pressure? The pressure can act kinda like an air shock, increasing the effective coil rate by increasing the pressure therefore increasing the ride height. I tend to see most people run around 150 psi. The nitrogen pressure will also affect your compression and rebound characteristics of the shock. Once you find out what you have for coil rates write them down in a notebook and take the jeep for a ride down a rough dirt road, try to get it up to 45-60 mph and make notes on how it drives. Are you bottoming out? (too soft) does the front or rear end feel squarely where it is dancing side to side? (too stiff) Does it feel like the rear end is bucking you? (too stiff) Or does it have a good ride? (right on) After that add 1.5" of preload and do it again making notes on ride. See how it changes. Also note where your rate rings are set. In the end if you want a generic coil over set up buy the Rebel or EVO kit and settle for the ride. If you want to take advantage of what you can get out of the coil overs then it will take some tuning to really get them dialed in.