Have changed exhaust manifold Gasket .... No difference.

I have more than enough back pressure to Rule out the Cat being blocked.

Driving it to town today and Noticed on my way back it got some balls from somewhere and had some go, the reason i noticed this so much was not only did it pick up with more throttle response but the "Blowing" wasnt as noticeable, Also the engine note completely changed from a flat single note to an almost V6 sort of sound ...... Starting to think about the VVt in more depth, only problem is I dont really muck around with the VVt side of things so not certain where Wiring/Solenoid or if infact it is atall working and the engine note changing is the VVT kicking in and then stopping working again?

It is very confusing to say the least

Any other ideas or previous experience in this issue?

A bloody nightmare hey Seddo .... Have you got any further with yours?

JAY