This spring kit is designed and developed in Australia by Crow Cams and is a direct replacement using the chrome molly retainers supplied in the kit. Heavier springs are required to run higher Boost. The installed height is 1.52″, the installed pressure is 105 lb, the pressure @ .5 lift is 205 lb, max lift is .60″, solid height is .89″ and is supplied with chrome molly retainers. 00037354