This is a free mod. This may, or may not have any effect on your car, it all depends on how the bypass is set. This simply adjusts the boost bypass to shorten it'* travel a bit. So you may see a bit more boost sooner.
First locate the boost bypass valve.
Use a 10mm wrench to loosen the bolts holding the valve in place, one on top.
And the other further down. Only loosen these, do not remove them.
Now adjust the valve down a little bit, and then tighten both bolts.
And your done.