Well it wont hold any sort of boost above about 9psi now, the needle just flaps around and the car jerks about just like the actuator is giving up or there is a split hose.
So today i've tried another actuator, taken all boost hoses off to check for leaks, removed my dump valve in case that was leaking and found nothing!!

You spotted the AFR curve
Yes mate it was, that was the way the metering head was setup for my old engine that was running 16psi and 200bhp. I hadnt altered it when i fitted this new engine, left it to TOTD to sort out as I dont have a WB lambda or AFR gauge!