I recorded my 0-60 speeds so I had a reference to go off, fitted lift pump and it seemed faster than before the lift pump, so was chuffed and thought it solved it, until I referred back to my recorded times and realised it was no better haha. I did have a boost gauge fitted and was reading 1.1 bar, this wasn’t at the manifold though was a T PIECE from the pipe from turbo to injection pump. The guy told me, he adjusted all 3, diaphragm, smoke screw on top aswell as the star wheel and then that is when this problem occurred and so he left the Land Rover parked up and scrapped eventually (that’s where I acquired the engine). So, I have not touched the injection pump as of yet, he did tell me that the little plastic collar that sits inside the diaphragm spring has been removed so just waiting to get my hands on one so I can try get the pump back to “standard” and go from there. Like I said, acceleration up to 30mph is faster than a standard 300tdi, yet anything over 30 it starts to lose power - 0-60mph in 31 seconds.. I have checked literally everything I can think of, smoke tested full intake system, removed the pipes and inspected visually, cleaned intercooler, wastegate is free, pipe to wastegate is fine, pipe to injection pump from turbo is fine…and loads more. Im at the end of my tether with this Land Rover now, the problem is where I’m located Land Rover specialist are either a fortune or cowboys! Sorry for the long message