thanks heaps guys for all you imput... turns out was paint scales from cross over pipe... as for vale spring how do you test them

Mate go to MTQ aka Mr Turbo he is in Gaven which is near the smith st off ramp on way to GC he rebuilds your turbo and puts a new front housing waste gate mod and new bearing setup. He did mine and have not had it on the car yet but have only heard good things about him. It cost me $1799 but is best value if staying with original manifold and can handle up to 30psi and produce up to 480rwkw.

Tell him what has happened so he knows the whole story.

With the valve problem ring Lee at Real dyno performance he is pretty much the guru for these cars

U can't test the springs till their out but from what your saying it sounds like that's the problem, if your running 10 to 15 psi and the spring haven't been done that's more then likely it.