Conical Springs are designed to provide a linear spring rate from free length to solid height while tapering from a 2.5” ID to a 5” OD. They have a 5” OD like a conventional rear spring at one end and a 2.5” ID at the other end as is used on the most popular coil-over springs. The 5” OD body diameter helps prevent bowing issues on these long, light-rate, high-deflection springs. With the proper hardware, they can be used as coil-overs or conventional mount springs.
The 95#/in and 110#/in springs are offered in 18″ free lengths. The 125#/in springs are only offered in 16″ free length. Free lengths were determined to provide the maximum usable travel and spring load without having the ride height too high in the rear.