hey yall. so ive had my 2000 s40 tuned. its running 10-11 psi boost. or at least it should be, but it never quite gets there. im thinking my CBV spring and wastegate spring were too weak and were opening to easily. how do you figure out what spring psi rating to use for your boost?

am i right in saying that you dont run a 10 lb spring for 10lbs of boost? you would want the spring to be the psi at which you would want the wastegate to start opening at correct. what would that psi be for a system running 10-11 psi? maybe like 5? i think stock is 2.5? any help on this would be awesome!

 

https://www.amsperformance.com/cart/...e-springs.html should help

Assume the stock waste gate is designed for 7-8 PSI boost