AFE Magnum = slammed Filter Minder?

[ntenna]

Just installed the full AFE Magnum Force kit, swapping out my stock airbox. Previously I had a (dirty) AFE drop-in in the stock box.



Here's the mystery: my stock '03 Filter Minder (known for its great accurracy?!) showed minor restriction with the old set-up, even when I dogged it.



So now the very same Filter Minder is mounted on the AFE intake tube, and after a couple of spins around the block with my foot in it, it's slammed more than half way down.



On the other hand, the truck is really kickin', a very noticable notch up from before. What gives? Any of you folks run into this? I seem to remember that DC changed the FMinder to a different calibration on the '04's, but my really good parts folks can't find the number and it seems to have dropped out of the parts list???



Any comments appreciated... ...

 

[SRadke]

My Magnum Force (with PG7 element) pulls the minder down to nothing. I'm talking all the way to the bottom. It has always done this since it was a stock truck with a paper filter. Just treat it like the mother in law and be happy you own a Cummins



-Scott

 

[Big MAK]

The rapid motion of the intake air across the pickup tube for the minder creates a vacuum in the pickup tube and has nothing to do with restriction in the filter. Think about the principle of lift of rapid air moving across an aircraft wing.



Putting the minder on there is just a convenient way to plug the hole. Don't bother read it.

 

[ntenna]

Thanks, guys. Confirms my suspicions. Maybe a nice rubber plug would look good there?

 

[ScottBrown]

I agree with Big Mak I dont even pay any attention to the minder. have the same setup. Filter minder just plugs the hole in the AFE. You would be more concerned with boost than the filter minder

 

[DLeno]

yea, there are two issues:



1. the 03 filter minders are not calibrated correctly (weak spring). there is not nearly as much real restriction as they indicate



2. We've established mathematically that the filter minder will show more restriction mounted in the tube than used in the factory air box.