Fact is I don't know how much mine moved, only that it did in fact move, and I don't know what the pressure is for sure. I did notice an improvement after I did it, but I also was having the crud in #1 plug problem at the same time so I cleaned that out and replaced the plugs. Prior to doing those two items I had been experiencing off idle hesitation and a ragged idle. Both have never returned. IMO, the only way to do this thing is to crush it then measure the pressure change, repeat until you get it where you want it. Me, I chose to use the dumb luck method which just happened to work for me.