Wastegate spring/opening problems

[BigBADGSX]

Background: I have an fp evoIII 16g with tial 38mm wastege and buschurs new inline mbc. Well as i went to set my psi the car kept spiking past 20lbs. I took it to the min and max on the mbc and yet, no change in my psi occured. Next, i took my mbc off and just ran it to my wastegate(ever since the rebuild i have yet to really hear my wastegate open up). Well as far as just testing it through the wastegate boost it spiked past 20lbs.
I believe that the spring in the wastegate is to big. Therefor im curious if this is the problem what spring i should get. http://store.forcedperformance.net/merchant2/graphics/00000001/data/w3_tial_38_sp.pdf here is a chart of springs. Does the psi of the spring mean when the wastegate actually opens or the psi you're running??????
i'll be running anyhwere from 16-22 psi after my tune.
Please give me your thoughts
thanks,
kyle

 

[500orbust]

The spring would dictate what boost you would be running without a boost controller and just the side port hooked up. If you want to run 16 to 22 psi, then a ~15psi spring will work best....This would be the large blue spring

 

[BigBADGSX]

ok, thanks man. I was just confused as if the spring was set to open the wastegate or not.