On street use do we need a preload, zero load. How much normally,4mm???. I know it is set by the factory I just want to check it if it too much.

 

From my experience of coil overs on other cars the answer is very dependant on the spring rate and spring length & the shocks expected spring platform adjustment range, desired ride height (if set by spring platform and not shock length). So how long is a piece of string in effect .