Hey, got this problem, I'm not getting full boost (18psi) in first gear, only getting 15psi. When I switch it to low boost (15psi) I only get around 12psi in first gear. I can hear the screamer pipe from around 9 psi on the high boost setting.
The wastegate spring is 1 Bar, Ive pressurized the intercooler piping up to 24psi and there are no leaks.
I can't remember if it was like this when I got the car tuned as I don't really drive the car.
Mods:
RB25DET Neo
GTX3071R
Link G4
50mm Turbosmart wastegate
6Boost low mount twinscroll Manifold