Make sure your solenoid isn't stuck closed. With controller off air should flow freely through it. Then check that you don't have a boost leak in the lines somewhere. Pressurize the system where you tee'd off for the solenoid and make sure all that plumbing is air tight.
Antihero
Putting AMS garbage, and $500 ebay wheels on a Z is like dressing a Victorias Secret model in a Walmart dress and Payless shoes. You're embarrassing yourself.