To tell you the truth I have no clue. All I know is that it worked for me. What I think is that the valve might be slightly open ( as you screw the nuts away from the clamp) but there is still plenty of pressure to boost but it take longer for the electronic to realise or reach the max pressure so the boost might stay longer? But again, I need to be honest, I haven't got a clue.
Next I might look for a spring, that will fit on the rod, this will certainly increase the pressure as the valve will be slightly delayed to open fully.
How's your car?

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E300TD year 2000. RUSTY SOLD
cost a fortune to maintain on the road
but run well on WVO
Second Merc died due to corrosion ( NOT rust) How can mercedes get away with that for so long?
Third lasted a month then went away...
Fourth now... Corroded too...