did you fix the issue? What was the problem.

 

I sure hope so, that was 4 years ago.

Are you having creeping issues as well? A few PSI on a large turbo with a small spring in the WG is pretty common. I had a 6 psi spring in my WG when I was breaking in the motor and it would see 9-12PSI up top.

 

If you are experiencing boost creep then you are not bypassing enough exhaust around the turbo. It is either an issue with how the piping is configured and/or the wastegate is just too small. Most likely the wastegate exits the pipe at a 90deg angle, which does not provide optimal flow. This is fine if the wastegate is oversized, but when you are on the edge then the wastegate tube needs to be angled in the direction of the exhaust flow. Easiest fix is to step up to a 60mm gate.