CM2250 Poor fuel mileage

[730Industries]

I have the exact same issues with my boost minus the awful fuel mileage. My dash matches doing fuel consumption by hand. but my boost holds hard at 30 up to 1500ish rpms and then drops to 22 or so by the time i hit 1800 rpms.

i had RR put a base tune on it after i got rid of all the junk and i got about 5.3mpg pulling 34k cross country with some really awful headwinds at 70mph at 1590rpm. So it wasn't completely bad. But empty i am barely getting 7.3mpg at 65mph at 1450rpm.

curious if its a combination of winter weather and the speed i drive?

the boost problem is my biggest issue. It has done that the entire time i've owned the truck. before i got an inframe. After i got an inframe. before and after RR did his tune. It's like the truck doesn't like going over 1500rpms to produce any boost.