That 550# was a generic statement, that cover like 10 manufacturers.
I ran the 450-580# Eibach, then moved up to the 650# BBK linear ones (a wee bit much for the street).
Now I run 425# coilovers which is like 850# (or 1,600# depending on who you ask) springs.
Not knowing any specifics, I stated some generalization. Now you wann build a corner carver, or a 10 second stip car, or a daily driver... I got different answers!
