Do some research on the Tein Basics, first. They like to stick the spring rate way up there. That makes for a horrible ride on anything but smooth pavement. This is the main reason that people think that coilovers ride like ass. Example, Teins for S13: HA's = 6k/5k, Flex = 5k/4k, Basic = 6k/6k! Just for a control, the stock S13 springs are 2k/2k.

BTW, 1kg/mm = 56 lb/in

Happy researching!