Filter Minder - what does it mean? - A

[Gary - K7GLD]

Ever wonder about the accuracy of your Filter Minder attached to your air cleaner and what the various markings on it translate to in common pressure values?

Related to that, are the references to "PSI", "inches of vacuum", "inches HG" and similar units commonly used in various atmospheric measurements - some of us get careless (including me!) in making pressure references, when actually there are vast differences in units between PSI and inches of vacuum, etc.

Here's a handy conversion table, displaying the relationship between 1 PSI and various other common units of measure:



As can be seen, there's a substantial difference between them!

I wanted to point that out before starting with the following demo of readings taken on my own '02 truck's Filter Minder, so a proper perspective could be arrived at.

Below is the zero reading as displayed on my own vacuum pump designed to bleed brakes and test emissions devices, it reads in "inches HG", and as can be seen, the Filter Minder is not yet deflected



And here is a shot with the Filter Minder at full deflection - and the vacuum gauge indicating about 2 inches HG:



From this, a reasonable estimate can be made as to the readings on the Filter Minder between zero and 100% - and as can also be seen, at least for my specific Filter Minder, 100% occurs at about 1 PSI flow across the filter element itself - or about 27 column inches of water. This is the point DC recommends that the filter element be changed.

There are a number of related points of interest as far as atmospheric pressure seen at the intake of our engines is concerned - such as the actual measured efficiency of various aftermarket air ducting and filtering devices as compared to the stock setup - what do they actually provide in improved performance and efficiency - and are actual figures/comparisons even provided?

In my own case, the stock OEM filter on my truck when it was new seemed to perform properly while the truck was stock - but as soon as I installed the Edge Comp and headed up a grade towing our 5th wheel RV, the filter minder immediately pulled down 2/3 of the way!

It was obvious that the added power and turbo boost provided by the Comp demanded better airflow!

I subsequently drilled the air filter box for increased air flow, and installed a K&N filter - and had no further issues. Later, I switched to the even better BHAF filter.

SO, it might be a good idea to get our airflow terminology straight, take a few measurements - and ASK a few questions when casual claims are made as to "better air flow" and "increased power" - talk is cheap, seat-of-pants reports aren't worth the rivets in your Levis - and actual figures are worth GOLD!

[Duluth Diesel]

So with a new stock filter on a stock airbox, how many CFM flow through before you would hit 27 inches of restriction?

This is good info, Gary. I find it interesting to see how much restriction it takes to yank down that filter minder. I also am intrigued that some of the new 3rd gen trucks can pull their filter minder down in stock engine form. Maybe DC should have upgraded the airbox to go with the new factory output levels.

I went and looked at the CFM and restriction ratings of the Nanofiber air filters. The smaller 4090 Nano is rated by AMSOIL to flow 1,000 CFM at 16 inches of water. https://www.amsoil.com/lit/databulle...1_rev10_06.pdf

Knowing that, 4090: 1,000 CFM @ at 16" H2O, care to speculate with me as to what the larger 4510 would flow?

Nice work as usual, Gary! :thumbsup

-Chuck

[Dr. Evil]

oooohhh, Gary youre so scientific...lol.

Nice writeup (as always)...:thumbsup


PS, ya look a little like Jack Sparrow.

[Gary - K7GLD]

Yeah - I'm pretty convinced the OEM filters pretty well SUCK - and ours seem better than what I have seen other makes supply!

16 inches of water would pull my own Filter Minder about half way - and is slightly LESS than that first hard pull with my Comp did with a NEW OEM paper filter!

NOW, what I'd like to have access to, is a high-volume flow source to actually measure the 3 filters I have on hand...

[Gary - K7GLD]

Originally Posted by Dr. Evil

PS, ya look a little like Jack Sparrow.

Funny you should mention that - my hairdresser keeps telling me the same thing, who IS Jack Sparrow, anyway?

[Duluth Diesel]

Originally Posted by Gary - K7GLD

NOW, what I'd like to have access to, is a high-volume flow source to actually measure the 3 filters I have on hand...

That would be interesting to see.


16" would pull your filter minder down half way, but I wish we had the CFM data. At 16" restriction, how many CFM is the stock filter flowing versus the 4090 and the 4510. That is the key.

[Gary - K7GLD]

Originally Posted by Duluth Diesel

That would be interesting to see.


16" would pull your filter minder down half way, but I wish we had the CFM data. At 16" restriction, how many CFM is the stock filter flowing versus the 4090 and the 4510. That is the key.

WELL, in my own case, and the stock filter housings, the housing itself can be a major restriction because of how it's designed - regardless of how good the element itself is...

[Duluth Diesel]

Originally Posted by Gary - K7GLD

WELL, in my own case, and the stock filter housings, the housing itself can be a major restriction because of how it's designed - regardless of how good the element itself is...

Oh that is certainly understood, so I'm in total agreement there. Heck, I've seen, and TDR did a 1 page writeup in the most recent TDR mag, using a stock 3rd gen airbox. They tested multiple filter minders and drop-in filters. The AMSOIL Nanofiber drop-in was the only one that didn't suck down the filter minder. This Nanofiber stuff flows!

In my experience, on a 3rd gen truck with a stock airbox and a stock paper filter, the paper filter is the restriction point. One the same truck, but with a Nanofiber drop-in, the airbox becomes the restriction point since the Nano can now flow better than the airbox will allow. That is why guys will "swiss cheese" their airbox to compliment the Nanofiber drop-in. It makes a great, simple, affordable improvment in airflow for stock to moderately bombed trucks.

There are also drop in filters for the 2nd gen air boxes.

-Chuck

Like the Doc says......good job as always Gary :thumbsup

Thanks for taking the time for this experiment and write up.............looking forward to more info if you can get a flow device to make it happenI am moving this to General Tech Articles

[Gary - K7GLD]

That is why guys will "swiss cheese" their airbox to compliment the Nanofiber drop-in. It makes a great, simple, affordable improvment in airflow for stock to moderately bombed trucks.

YUP - been there - done that!

[Duluth Diesel]

Nice pic! That's what I'm talkin' about.

-Chuck

[DrDiesel1]

Originally Posted by Gary - K7GLD

Ever wonder about the accuracy of your Filter Minder attached to your air cleaner and what the various markings on it translate to in common pressure values?

Related to that, are the references to "PSI", "inches of vacuum", "inches HG" and similar units commonly used in various atmospheric measurements - some of us get careless (including me!) in making pressure references, when actually there are vast differences in units between PSI and inches of vacuum, etc.

Here's a handy conversion table, displaying the relationship between 1 PSI and various other common units of measure:



As can be seen, there's a substantial difference between them!

I wanted to point that out before starting with the following demo of readings taken on my own '02 truck's Filter Minder, so a proper perspective could be arrived at.

Below is the zero reading as displayed on my own vacuum pump designed to bleed brakes and test emissions devices, it reads in "inches HG", and as can be seen, the Filter Minder is not yet deflected



And here is a shot with the Filter Minder at full deflection - and the vacuum gauge indicating about 2 inches HG:



From this, a reasonable estimate can be made as to the readings on the Filter Minder between zero and 100% - and as can also be seen, at least for my specific Filter Minder, 100% occurs at about 1 PSI flow across the filter element itself - or about 27 column inches of water. This is the point DC recommends that the filter element be changed.

There are a number of related points of interest as far as atmospheric pressure seen at the intake of our engines is concerned - such as the actual measured efficiency of various aftermarket air ducting and filtering devices as compared to the stock setup - what do they actually provide in improved performance and efficiency - and are actual figures/comparisons even provided?

In my own case, the stock OEM filter on my truck when it was new seemed to perform properly while the truck was stock - but as soon as I installed the Edge Comp and headed up a grade towing our 5th wheel RV, the filter minder immediately pulled down 2/3 of the way!

It was obvious that the added power and turbo boost provided by the Comp demanded better airflow!

I subsequently drilled the air filter box for increased air flow, and installed a K&N filter - and had no further issues. Later, I switched to the even better BHAF filter.

SO, it might be a good idea to get our airflow terminology straight, take a few measurements - and ASK a few questions when casual claims are made as to "better air flow" and "increased power" - talk is cheap, seat-of-pants reports aren't worth the rivets in your Levis - and actual figures are worth GOLD!

So when you drilled the air box, did you measure the change/reduction in restriction before you replace the filter with a K&N....? If so, did the venting of the air box change your readings. I run the Amsoil Nano drop in, have not modified my air box and run a Cool Hose intake tube. The filter minder shows very little pull down. This is with the TST on 3-3 and tests on 4-4 @ WOT....