Hp one day but not the next
 

On. My 03 2500 Smarty Touch 50 hp injectors, FASS, HE351, I have been having a problem with the truck having good power one time I drive it but not the next. Under good conditions I will see 38 psi and 64% load. 24,000 psi rail pressure. Under low power I have a hard time getting to 30 psi but if I rev it high enough I can get 35psi. It maxes out at 47% load. Boost pressure on touch matches analog gauge. With it having power one day but not the next I'm kind of frustrated in tracking done the problem. Usually it's air or fuel. If you are lacking one or the other your hp is limited.

Not sure on the prob.... Just a thought on the turbo; do you have the waste gate turned on? 351 has the elec waste gate, as your Ram came with the non-elec waste gate.... I have the moded 351 on my truck and with the waste gate turned OFF, i had way high drive pressure! Small exh housings need a waste gate!
Hope you find your prob!

38 PSI is a little high for that turbo. Is there any codes? You go through your engine bay and check grounds, battery connections and fan clutch wires?

Yes 38 psi is high. It's a modded 351 with 70/60 turbine wheel. I need a wastegate actuator set to 35 psi. I found the problem. When my speedometer quits I have low power. The engine goes into derate with 0 speed. I have a different turbo to try here as well. I rarely take the turbo to 38 psi. The odd time it's nice to have the hp.