Diesel Bombers - 46" Chevy Suburban with 12v Cummins ( Iceland ) fuel/boost problem

Hi guys.
Im new here and writing from Iceland.

I have a 1987 Suburban on 46" Tires , nospin front and rear , air suspension , two transfer cases , 5 speed manual / 4link etc etc.

The engine is from a 1990 DAF truck and has Lucas Cav fuel injection pump.
I was hoping someone here could tell me how to up the fuel on these pumps?
I only get 0.4 bar ( 5-7 psi ) boost at full load , no black smoke or anything.

It has a new diaphgram for the boost ( located at the side of the pump )
New HX40w turbine ( the problem also was before the new turbo )

My question is: How the heck do I turn up the fuel on these pumps?
Turn in the pin in the diaphgram?
On the cover for the diaphgram there is a copper lid that I can turn in or out and it says AIR next to it. Does turning it in or out make any diffirence ?
Behind the diaphgram where the fuel pin is put in there is a mark or something for a screwdriver and i can turn it ( some kind of starwheel ? ) Should I turn it in or out ? I will try to include a picture
Is there somewhere another adjusting screw ?
I was hoping someone here could give me some advice , because taking this lid off is a horror. The bottom screw is a b**** to get in and I dont want to do it more often than I have to
Best regards.
Karl https://cimg2.ibsrv.net/gimg/www.die...f173c7023e.jpg
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