I just spent all day installing a new efini y pipe, replacing the belts, replacing a broken coolant hose to the turbos, and replacing the radiator hoses with silicone ones.

I found a few broken / cracked secondary turbo hoses when doing the y pipe install, so I replaced those.

I took it on a test drive and it performs perfectly under light driving conditions (no boost).

It takes off from less than 3000 rpm to 7000 in a 10-9-13 boost pattern. (what would cause this?? i dunnoo.)

When flooring it from like 3500 or 4000 rpm in second or third it only boosts like 5 psi according to my boost gauge. Sounds like a boost line issue? probably. But here is the strange part. After letting off of the gas there is a mechanical "wind down" sound (it actually sounds really cool lol). It does not make the sound when it does not have the boost issue.. only after maxing at 5psi.

Any ideas what the sound could be?
Why my boost is so high?

As always ANY input or thoughts are beneficial.. Thanks in advance