Max 7lbs problem
 

Searched and read many topics relating to this and tried each of the solutions found to no luck.
Boost sees 7lbs perfectly. No creep no spikes. No matter what I seem to try I cant get more out of it. Friends have very similar set ups and same turbo etc. and none seem to have problems with this

B18a1 stock.
walboro 255,
dsm 450's
T04E turbo
38mm wastegate
2.5dp to gutted cat and 2.5 pipe all the way back.

No leaks in or out. pressure tested the charge pipes to 22lbs and no leaks with boost gauge reading it correctly.
Tried multiple variations with boost controllers and different lines before and after the wastegate diaphram no luck. Changed WG springs with various springs from friends all rated up to 20ish lbs or so, still nothing.
Hondata s300 with boost cut off etc.

I'm sure there's other things Ive tried that someone will mention but cant think of them atm.
Runs great in every fashion at 7lbs. but looking for 14lbs before taking it to tune. really dont think its the limit of the turbo being how friends have it too running much more than 7lbs. Any help is appreciated.

What if you put a block off plate over the wastegate? How much boost would it make then?

Just be careful and lift if you get too much!

off hand i can think of a few. restriction at intake, restriction in exhaust, boost gauge failing. leaking wastegate and/or internal failing turbo. did you forget to install the wastegate valve seat? its a metal ring that seals the wastegate valve to the wastegate body.