Im going to pull the trigger on a new tubular k member and im looking on uprproducts.com website and i had found one that i would like to purchase but i just have a question about the spring rate, my car came with lowering springs when i bought it, so how can i figure out what spring rate i need, the options are 130, 150, 175, 250, 350 and some have 12-250 and some are 14-130 so i can only figure that the 12 or 14 is the spring length, can somebody help me with what they have purchased and how they like it and what brands to stay away from, thanks guys