Low boost

[Dsl_Dog_Treat]

I have been working on trying to figure this one out.
At first run, I could only get 2-3 lbs of boost from the turbo and no power gain felt.
Pump was turned up before the install and can get some good smoke.
The first thing I found which would have corrected the problem was a leaky fitting on the up pipe.
I welded the pipe as a clamp would not solve the issue.
It then allowed the turbo to build almost 7 lbs of boost while standing on the throttle rowing thru the gears.
Now with the camper on the back of the truck, I can only get 6 lbs of boost and really cannot feel a power difference from being and N/A truck.
The turbo has around 90 k on it and was checked out ok by a reputable turbo rebuider.
What might I be doing wrong here.
Everything seems to be in order.

 

[argve]

check entire system from exhaust mans to intake man for leaks - if leaks at found plug them up. I know that you won't see this before arriving here at the campground but figured that I would go ahead and post it so that in case someone else has a problem (but not posting about it) they can go out and check their system...