i was reading some text from ford-trucks.com and a fella had said he shimmed his turbo. what in exactly does this mean? and is it possible to do to my PSD?

 

Are you sure that's what it said? I've shimmed my fuel pressure regulator, but I've never heard of shimming the turbo.

 

What does shimming the fuel pressure regulator do for you? How is it done?

 

Shimming the fpr is only done on the older trucks like mine. The SuperDuties have a different fuel system, so shimming isn't possible. What it does for us with the older trucks, is increase the fuel pressure, which will give better throttle response.

 

how would a guy go about shimming his fpr?

 

Take off the engine cover, and on the right side of the fuel filter housing, you'll see the fpr. On the right edge of that, there's a large brass nut. Remove the nut, and inside, there's a spring. Here is a pic of the parts involved. In the picture, there's a cup that the spring sits in. That won't need to come out of the housing.
Some people use a BB which is put into the cup before the spring is replaced. I used a cap screw. I inserted the threaded end into the spring, and then inserted the screw/spring assembly into the cup, screw head first. Once that's back in there, replace the large brass nut, being sure the nipple on the inside of the nut is centered inside the spring. Once it's all tightened down, check the fuel pressure at idle with a tire pressure gauge at the shrader valve next to the brass nut. Ideally, the fuel pressure should read between 70-85 at idle. I like mine at 72. If you find the pressure to still be too low, you might need to add a washer to the end of the screw, so it compresses the spring more. The six corners of the nut will have to be removed, so it will fit down inside the cup.
Whatever you do, don't adjust the pressure over 85psi. That would lead to premature failure of the pump. From my own experience, I've found shimming to improve throttle response, and improved the idle. Once I got my pressure up near 85, my idle got "lopey", so I brought it back down to 72.
I hope this helps.
(Remember, this only works on pre-99 trucks.)

 

Do all the pieces come out, like in the picture? I was reading on Steve Baz's website how to do this, and it's not clear how easy it is to undo the procedure. I like to be able to easily undo things, if it doesn't work right.

 

Diesel-Lady- All the pieces might come out, though the cup at the bottom sometimes doesn't. If you want to get the cup out, you can pull it with a magnet. Reversing the procedure is as easy as doing it in the first place. If you use the cap screw or BB, there won't be any issues with reversing the procedure. If you use the cap screw and need to add a nut to the screw to increase the pressure, be sure to file off the corners of the nut to bring the size/shape of the nut down to match the head of the screw as shown in this picture: click here. I found nylon nuts, which made the filing much easier.