iirc the springs have psi ratings
something like green for up to 15 psi
yellow spring for up to 25psi
then the other two springs are something like blue and red iirc and there for up to 30psi and 35psi or something.
so on a un mapped mk4 you should have a green spring otherwise your dv will not be opening proberbly. stage 1 you will be able to get away with green or yellow depending on how high boost your running and stage 2+ you will require yellow
go on the forge website, iirc you can buy them for not much