Lack of power....
 

I seem to be lacking in power, I can put the pedal down on the floor and it does not even act like its floored, no black smoke even appears, it doesn't take off and fly like it could, my dad has a 95 with a 6.5, his is a 1500 and 3.42 gears, mine a 2500 so I assume its 3.73 gearing at least, but his will freaking take off way better than mine, I know that not all are the same but it should not be that much of a difference, he has 40,000 more miles on his. I have done the LP test, it holds a steady 5 psi, checked it through to 3,000 rpm and even that high it held a steady 4 psi, the IP is a -5288, its not original, I've already gutted the CAT as it was plugged up completely, it just doesn't seem to have the power it should, you would at least expect to see some smoke, but theres nothing, it runs fine, I was curious as to the timing, my uncle brought a tech 2 over, the timing is at -1.85 currently. The injectors are new, not even a thousand miles on them, air filter is clean, turbo and vac pump work fine, PMD has been relocated, fuel filter is new. Yall got any ideas?

whats the year? if its above 94, its could be a bad throttle positioning sensor, bad OPS, or the sock in the fuel tank could be bad
just throwing out some optioins

You talking about the Accelerator Pedal Position Sensor? I haven't checked for codes in a few weeks, but last time I did, I didn't have any for the APPS, I had a couple for EGR but that's due to it not being connected, I've thought about replacing the OPS, the previous owner said they had replaced a "oil pressure something". They weren't exactly knowledgeable on the beast they were dealing with. It doesn't look like it was recently replaced, so I may go ahead an try that, my dad seems to think its not the sock, I think its possible but don't want to have to pull the tank to do it. Oh yeah, its a 94.

mine did that and the sock was bad in the fuel tank, and it burnt out the lift pump then it would stall all the time.