I have a 2011 r59 jcw n14...
I got my forge bov and it cane with 2x springs , a blue and a yellow . I believe I installed the yellow ( the less stiff spring ) and am wondering which I should use with my car.
I will have full intake and upgraded ic piping, bigger ic , catless down pipe , upgraded coils and step colder plugs along with a custom tune..
so should I run the stiffer spring or should I stay with the yellow one ?

 

Pretty sure the Forge design uses boost pressure to hold it closed, so the spring pressure shouldn't matter much. I know they have different spring rates, but I don't think anything other than the base spring is needed. I think I'm running the yellow spring on my stage 2 tune, and never even had a hiccup from it. In theory, you want the least amount of pressure on that spring, so that it stays closed under boost, and opens when you want it to. If the spring is too stiff, it won't open when you let off.

 

thank you..
I did find what color is for what psi so with my mods and tune coming i went with the yellow which is a 15-23psi spring...
I just don't wanna damage my turbo befor I have a change to upgrade it because i know these jcw turbos are a great grab..