HI All

An update on my 450 SLC project.
I ended up flushing all the fuel lines , new fuel filter, pump and a got a working GFD of another merc 450 slc. Fuel tank was flushed and high pressure cleaned.
I am getting at least 3 litres/minute when I do the fuel volume test at the supply line to the FD.
The car starts perfect and idles at 750rpm. When I press the accelerator it increases the rpm with good response, although a bit rough.

However when I put the vehicle in drive and try to move it , it moves but only just and cannot even drive over a small hill.
So essentially no power.
The fuel metering plate feels a bit hard when it is depressed. But this came of a working car, took it off myself, and the plunger piston is moving freely.
Please assist with your thoughts on how I can trouble shoot and resolve this problem.

Will appreciate all your help, I am on vacation and would like to at least drive this car for a few days.

C