Setting point higher yielded the 15 you where looking for.
Did it run any faster? More mpg? Better 60?

Try moving reference point. See if that does anything for you.
We stock the 74/75 and can get the 76/76CEA pretty quick.

 

Setting the point higher was able to hold 15 but when I do that at low rpm it made the 18 it was supposed to. Then dropped to 15 at high rpm shifted hit 18 again the instantly started dropping to 15 again. I'll move my reference and see what happens

 

Referenced the waste gate off the intake and now holds 15 pounds without batting an eye. Thanks for the input guys

 

Kinda hijacking this thread now....

I was having a similar problem when my truck was getting tuned, boost went to 7 and dropped to 4 in the top end, I got a heavier spring and have yet to being it back to the tuner. But Im referencing the WG off the port on the TB that used to go to the valve cover, would I see a difference if I ran it to a port on the manifold? Because that port is before the throttle blade

 

I run the WG, BOV, and cab gauge (via MAP) off the hose to the power brakes... no issues here