I built a 72~ or so mm MAF draw through tube for my ATP 30r.. and it pegged out with the stock TMIC. That was with 28-30 psi with around zero degrees air.
In the summer with 60-70 degree intake temps it wouldn't go past 4.88 volts; I bet it's even worse now that I have a HUGE front mount. I'll be moving the MAF flange to a bigger tube (3.25 inch??) blow through here today when I borrow my buddys tig welder.. and we'll see what happens.