I am very new to the diesel world, just bought my first one about a month ago, a lifted 2006 F250. Other than the lift its pretty much stock other than an Airaid cold air intake and a 4" turbo back exhaust. I have been doing research and trying to learn as much as possible. I just got a SCT Livewire TS from Innovative and got a couple custom tunes from them. I loaded up the Xtreme Street tune and it is a night and day difference over the canned tunes! It is noticeably faster, drives better, and doesn't pour black smoke. However I noticed even with the Xtreme Street tune the boost level only goes to around 22psi. When I was on the highway and rolled into the throttle it spiked at 26psi. On the stock tune it is around 22psi. Is it normal for it to be at the stock boost level with a custom tune? I have three buddies that have 6.0l diesels with tunes and they are all making 37-39psi, thats why I am so confused as to why mine is still at stock boost levels but still feels much faster than stock. I know there are other factors such as fuel, timing, ect...but I would think the boost level would be higher. Any help would be greatly appreciated!