Same question from me. I'm running stock w mass air meter and 11 psi

 

I'm using a 2.5 bar sensor for SD. You can only push a maf so far before it will max out which happened for me around 6psi. I also blew a maf in half at 12psi before I got a different iat sensor and removed the maf all together. I don't like using a maf at all for turbos since boost can vary with load so much. Superchargers are ok to point because the boost is always dependent on rpm which is easier to tune with a maf.

It looks like the guy that was selling the 2.5 bar sensors on tech got booted. Probably for not being a sponsor.

 

2 bar offs supercharged cobalt ss. Turning boost up to 12psi on my NNBS 4.8 turbo 08 Silverado

 

I think what I noticed is that the guys running the older trucks like the nbs have to use 2.5 bar map sensors cause their ecm's can't read the mass air at high HP. My tuner told me that he gets 800+rwhp tunes on the newer ecm's through the mass air. I'm getting my truck tuned tomorrow. Lets see how that goes with the maf.