AEM dry filter

[gmorley]

I have a 2002 LB7, with 4" exhaust. I have now installed a aem "Brute Force" intake system #21-8013dp. The filter restriction gauge now shows full restriction all the time. I reset it and stomp on the pedal it's back to full restriction. I called aem and they said because the velocity of air is now so great that there is a negative pressure being developed and that's what's causing the gauge to show a restriction instead of there being an actual filter restriction.

True??

[DmaxMaverick]

Hogwash!!

Restriction is restriction. The velocity would only be a factor with the placement of the orifice the filterminder is attached to. You could have an eduction effect if the designer of the intake pipe failed to take this into consideration. If their system increases the velocity, the intake pipe is too small (smaller than OEM???). The idea of increased intake pipe dia. is to reduce the velocity, and resultant restriction.

All else being equal, an engine at a given power level will require the same amount of air intake. The velocity within the engine will be the same. Intake pipe air velocity will increase with smaller pipe dia, and decrease with larger pipe dia. That's it. No more. If the filterminder orifice is allowing eduction, the actual restriction will be skewed, making it absolutely useless.

The only other thing that could cause what you are seeing is the filter element. If it is not flowing enough air, it will, in fact, be a restriction indicated by the filterminder.

[Ponderosa JT]

Here is an airflow calculator on S&B's website;
http://www.sbfilters.com/cfm_calculator.php
I thought this was interesting to know the CFM required for our engines. It's based off the displacement of the engine and max RPM. If the AEM cannot flow enough air the filter minder will show it. Where is the filter minder placed on the AEM system? Maybe a venturi effect? I didn't have the option (without modification) to keep the filter minder on the S&B.

Jeff

[streetwise]

Hey gmorly and DmaxMaverick,



I just saw this and want to chime in on this matter. We have had some issues with the Filter Minders pulling in and have a revision in the works. We normally see this when the intake is on a truck that has the wick turned up on it (chip, exhaust at minimum) but still not a normal occurrence. That being said, Ponderosa JT is correct, due to the location on the Filter Minder in the inlet tract we actually get a venture effect that can cause a vacuum (there is no such thing as a negative pressure, I

[DmaxMaverick]

Thanks for your reply, Streetwise. Excellent response to your customer's needs. Real customer service seems to be rare these days.

[gmorley]

streetwise

Outstanding, just the response I was looking for, I'll be on the phone shortly to see about the fix.
Sorry for the delay in responding, but life got in the way.

Thanks all

[streetwise]

The fix for this issue will be avalible in July.

thanks

Rick
AEM

[gmorley]

streetwise

Thanks, I'll be in touch in july

gord

[Ak_Stick]

I have a stock 03 d-max with the Brute force, and I have the same issue, I hit the gas, and it goes straight to require service.

[gmorley]

streetwise

Any word on the fix, I,m not having any luck phoning

Thanks

[killerbee]

return to stock. With 27 square feet of filtration material, the restriction will mysteriously disappear.