I dont know about changing the springs on the fx , the ride can be harsh enough (at least where I live) love the look , nice mod ! winter may be rough in the snow! Just ordered a stainless strut to strut bar that fits nice under the hood from stillen for $145. this will help with the front end flex and should help tighten cornering. sure it is a nice mod to add with spring mod and looks hot ! will get pics out when installed.