L9000 ford air filters

I have a couple l9000s they all use the same filter and it seems to work fine except for the one with the 3406….it needs more air than the filter will flow. Under load it will pull roughly 20 inches of water vacuum in the filter with a brand new one and peg the gauge once it gets a little dirty. Has anyone seen something other than this filter setup? Or have any good ideas?

 

That was my thought too but I have 2 guages and a pop button service indicator that all seem to be pretty close to each other
Maybe I need to find a different guage or make a u tube with hose and water

 

I suspect it might or possibly could use a larger turbo. There’s no issue with egt but at full load it leaves a thin black trail of smoke….nothing remarkable really but a possible indicator of not quite enough air

 

Max boost is between 32-40 psi depending on ambient air temperature and usually occurs around 1600 rpm and falls off above that to about 25 at 2000 rpm

 

Max boost is between 32-40 psi depending on ambient air temperature and usually occurs around 1600 rpm and falls off above that to about 25 at 2000 rpm

 

I can definitely make that happen
I will go get one next week
Did you still pull through the side of the hood or set something up to get it from out front