Ok...

So I built a high RPM tune (2006 LBZ). It fuels all the way to 4k (went through EVERY table that has anything to do with high rpm stuff). After doing my custom lift pump setup rail pressure holds up top now as well. But Boost is dropping off??

My tune is nothing crazy, but it makes around 25-26psi max in the 2500-3000 rpm area... and then starts dropping off... I am seeing maybe 22 at best at 3900. I played with turbo vane positioning to see what I could do there.... when opening the vanes up some (19-20 in the high rpms) I only saw 19-20 psi at 3900. When I closed them down a little tighter (around 40) I see 22psi at 3900...?

I raised my high rpm boost target tables up to around 26-27psi and that had no effect.

I used the timing calculator and targeted about a 45/55 split.

Truck seems to smoke worse up top too, especially with the vanes opened up (which makes sense) Was really hoping to see 24-25psi up top... seems like I have enough fuel, I'd like to make better use of it up there and also make a little bit more power (running this tune to keep out of 5th gear).. I aimed my tune at making more top end power and not a ton more torque (again trying to go a little easier on the trans)

Just looking for some pointers / advice?! THANKS!!!

(I am close to 7000ft elevation as well...)