Big thanks to Blake BSA and Jeremy dvs_jez for their help. These blokes are a legend and always willing to lend a helping hand even on a rainy Saturday.
The boost drop issue has been fixed. To everyone who's doubted the manifold and gate mounting position, keep hating cause it wasn't the issue.
My tuner was a silly mofo, he set the gain too high.
Jez had a look at it after swapping with his tial MVR incase it was my gate that was the issue but turns out it wasn't.
It now holds the boost flat to red line. Tested at 17psi and 21psi.
The whole experience has left me very disappointed in my trusted tuner whom I've used for the past 4years.
For all tuning needs on the central coast in syd, contact dvs_jez and for all fabrication work, contact BSA, he's based in the gong and does work there, syd and central coast.
Gotta love full boost by 3700rpm
It's going in for finishing tune at 21-22psi in 3weeks so will have dyno sheetsresults then.