a while back i installed a raptor lift pump and set the pressure about 28 psi, the next day it was only showing about 21 psi.... after driving for a couple weeks and watching all of this, it goes back and forth at start up, sometimes its 21 sometimes its 28, when its showing 28 i have now noticed that the engine feels very sluggish, slow too spool, runs very high egt's and smokes like a freight train on light accelation, but when its showing 21, i can barly keep the tires stuck to the road, and it runs awsome????? anyone got any ideas as to what the heck this might be?

 

Your pressures are all within spec.
I would verify that they are correct with another fuel pressure gauge.

 

the pressures are correct, verified with two different gauges and has a brand new autometer gauge right now, but its the engine operation i am worried about,

to try an explain a little better... the pressures i gave are a max pressure i will see untill another start up, for instance today i start the truck and it showes 28-30psi and will stay there all day and maby for a few more days and runs like crap, and tomarrow when i start it, it may show 21 psi all day and run awsome....

 

How do you have the injector return plumbed? I can't really see any common symptoms, being that I run 40 psi on both my trucks and no issues like you describe. I'd think the fuel pressure is a symptom as opposed to a cause to your troubles, but I can't think of what. Have you tried regulating the fuel pressure down to your 21 and see what changes?

 

i have the injector return t-ed into the injection pump return to tank, i havent tried lowering the pressure but before with my fass pump at 15psi, i couldnt get over 3200 rpm's.... idk maby im just crazy lol maby i got a wastegate sticking or somethin?