Not trying to rain on your parade but you need more information than you have. If you want to maintain your current ride height and get a better ride just swapping out a set of stock springs are going to disappoint you. If it was mine I would measure the installed height of the current spring. Then I would take them out and find a race car guy that has a spring rate tester. Then he can compress the spring to your installed height. Then he can further compress the spring and see if the rate changes. (it would be good to know how much suspension travel you have). Once you have this information call a spring manufacturer such as Afco or Detroit Spring and they can dial you in to a set of coil springs that will work for you.
Last edited by don stocker; 10/30/2014 12:51 PM.