massive reconfiguration time again.

Maybe I can borrow your forced induction boost gauge?
LOL, just some turbulence causing some uneven conditions which could be causing a lean condition up front...
You are not getting as much air as a nice "ram air" system. Like people that run a funnel system through the head light. Or a sealed carb to hood/hood scoop. And as far as turbulence, people try to get turbulence - - or vortex into the intake. Like certain throttle body spacers for that purpose..