boost level going up hill at full throttle?

[red2005ss]

I was coming from Bullhead city, Az going to Kingman, Az where I live at, and there is a 2000 ft pass I have to climb so i go up it full throttle. I have noticed lately that my boost level has been creeping up from 13 to 15 psi.
Should I start looking at my cat or does everyone else see this too.
I have 50,000 mile.
6 to 7 % grade.

[bc3tech]

that could depend on the elevation you were at... if you're saying it was creeping higher as you were going up the grade, well, that's odd.
not sure 'bout the whole cat thing tho :)