Okay I visted Lymington motors where they told me they had fixed another tuned car earlier on in the day. They were meant to check and adjust my EHA valve. When they eventually got the pressure tester onto the fuel distributor (it measures the upper or lower chamber pressure) the tool seemed like a compass, changing reading as you moved it. Anyway they seemed to establish that the pressure differential was only 0.3 bar when it should be 0.4.
They removed the valve and were put off by the screw which they though was the adjustment. The prats were trying to turn it clockwise almost rounding off the threads! I informed them that you undo the screw and an allen key is adjusted underneath. Bottom line was no change and really not much of an idea either except that they initially did a leakage test, all cylinders over 50% so I'm going to strip the engine down and do the rings. Also going to check for a vacuum leak by blacking off vacuum lines one-by-one.