I think we need just to remember... What we want to achieve is a steady Pressure Differential across the fuel rail through injector into the manifold. Let's call this P1
Fuel Regulator is Dynamic valve controlling P1 by applying manifold pressure on the diaphram. Let's call manifold pressure P2.
The third pressure is P3, which is the fuel rail pressure.
Mathematically "if" i am getting this right is P3-P2=P1
P1 is set at idling when we know P2 is at 0 value. At that point, P3, Fuel rail pressure is same as P1.
So... P3 is a variable. So is P2, but P1 need to be constant. That's the whole point of the regulator.
Whether it is at WOT, or highest at certain point can be true, but only circumstantial condition. Not absolute.
Rising Rate should be exactly as manifold pressure. I found out that a lot of cheapo' regulator is not. Speedchaser will know this first hand.. i have had at least two that i can donate for charity or scrap. Still shiny and both within 6 hours operation.
I think what speed chaser is trying to get when he say it bumps up to 7 bar is that he does that to check if the pump is able to push pressure above workign pressure. As normal, any engineered product is design with the safety factor of 2, therefore if the pump can push to 7 bar, i would say max working pressure is 3.5 bar. Please note this is P3. NOT P1.
So.. sit back.. chill and just drive lah bro.. what you and i want is just to shred rubber .. nothing to do with pressure... wanna think pressure better go take out the "R" from drive and go dive instead.
:)