Hey Beanhead if you still have the afe ill take it id like to see the comparison on my truck between my 6637 and the Afe stage 1.

PM me.

For an ISO-5011 test the "Dirt Filtering Efficiency" is given by...

"Dirt Filtering Efficiency"={"Dirt Holding Capacity"}/{"Dirt Holding Capacity"+"Dirt Passed"}

...and here's a summary for the 4 filters tested and filter #2) is the stock FA-1750 filter and it performed the best! The following were measured in accordance with the test: Pressure Drop for Clean Element, Initial Efficiency, and Dust Loading Capacity. See Page 7 for the CFM airflow versus Inches H20 restriction graph for a stock 7.3L FA-1750 filter. http://www.thetruthaboutfilters.com/...andAFE_Dry.pdf

https://h1.ripway.com/ernesteugene/DG5/ISO5011.jpg

The above tests for "Dirt Filtering Efficiency" and "Dirt Holding Capacity" were done by establishing a constant 628 CFM airflow through an initially clean filter and then introducing into the input airflow stream a controlled amount of "standardized dust" at a controlled Dust Feed Rate =17.58 grams/min. The "standardized dust" meets an ISO-12103 standard which has a specified distribution of particle diameters ranging from about 0.5 um to 150 um and the peak of the particle distribution curve is at a 60 um particle diameter.

Note in the above that about half of the "standardized dust" particles have diameters less than 60 um which means they're "invisible" to the naked eye so claiming this or that filter is providing a good or even an adequate "Dirt Filtering Efficiency" just because "my intake tube looks clean" is not an acceptable criteria!

The reason the stock FA-1750 filter tested the best is because it employs an "impregnated paper" element which is a required feature of any paper element if it's going to perform well in an ISO-5011 test! I'm wondering how many other "paper element" filters have the "impregnated paper" feature?

The "CFM vs Inches H2O Restriction" test was performed on a clean filter and these are the measured data points for the complete stock air inlet system including the air box and FA-1750 filter element.

CFM......Inches H2O Restriction
000.0.. .0.000
314.5. ..4.436
471.1.. .9.598
627.7...16.660
786.5...25.775
929.8...35.705

As can be seen in the above "CFM vs Inches H2O Restriction" table a 628 CFM airflow through an initially clean filter requires a suction which causes a 16.66" H2O Restriction across the filter. As the filter does its job of filtering out the dust that's been introduced into the input airflow stream the filter becomes progressively more restricted and the suction is increased so as to maintain a 628 CFM airflow through an increasingly dirtier filter.

When the Inches H2O Restriction increases to 10 Inches above the initial 16.66" H2O Restriction for a clean filter the test is terminated and the results are tabulated. The "Dirt Filtering Efficiency" represents the amount of dust that was stopped by the filter during the test and the "Dirt Holding Capacity" measures the dust holding capability of the filter. These tests are then repeated three times and the results averaged.

Well I don't think it's a good idea to... "factor in cost" ...because when it comes to their choice of an AF=Air Filter I think too many people are being "penny wise and pound foolish"! If you properly maintain your stock air box as I posted in several recent threads then it's perfectly adequate for supplying enough clean cool air for at least 300 FWHP or more. Don't replace it unless you upgrade to something that's been proven better in actual controlled testing!

Since this is a "cold air intake" thread I'll go ahead and post this comparison between an "open element" AF and a "cold air intake" AF here as well...

If you assume that there's 5.28 ft^3 of free air space available in a 7.3L engine compartment from the hood (closed of course) down to the bottom of the engine then this 5.28 ft^3 engine compartment air space implies that an "open element" AF which is sucking in a 528 CFM airflow to supply the engine sucks all of the available air out of the engine compartment 100 times each minute! Where does all of the needed replacement air come from?

It comes from the ambient air but thanks to the Ford design 100% of the ambient replacement air is forced to flow through a 140 F A/C condenser, then if you're at a sustained 18 psi boost it's forced to flow through a 160 F IC, and finally it's forced flow through a 190 F radiator and then it picks up even more heat from the exhaust manifolds etc.. and then it flows directly into your "open element" AF!

And yet people continue to claim that the air flowing into their "open element" AF is only 2 F or 20 F or whatever unbelievable (for me anyway) low number of "F" hotter than the ambient air is!

Now consider an alternative. if you're going 60 MPH=5,280 ft/min a "cold air intake" only needs to have a 0.1 ft^2 (3.8"x3.8") opening in order to supply an AF with a 528 CFM flow of "outside RAM ambient air" which no matter how you want to cut it is much cooler than the ambient air that's forced to flow through the A/C condenser, the IC, and the radiator!

In addition to being much cooler the "outside RAM ambient air" due to its RAM air effect also supplies the "cold air box" with "pressurized" air which reduces the restriction of the "cold air element" by 2" H2O.

This means there's two different ways by which a "cold air intake" reduces the workload on your turbo relative to the workload that's required for an "open element" AF... 1) the cooler air increases the air density at the compressor wheel and 2) the higher pressure air increases the air density at the compressor wheel.

Since MAF={(AD)(CFM)} lb/min an increased AD=Air Density lb/ft^3 means that it takes less CFM to provide a given MAF to the engine and less CFM means the compressor wheel rpm is lower for the same MAF. Conversely an increased AD means that more MAF can be provided at a given CFM.

Here's my recommendation for a "custom" exhaust. It provides the minimum restriction to flow, you don't have to worry about high hitch weights causing it to smash against the rear axel when you hit a pothole, and it's easy to see your smoke!

https://h1.ripway.com/ernesteugene/DG5/1Exhaust.jpg

https://h1.ripway.com/ernesteugene/DG5/2Exhaust.jpg

Gene what is that in the pipe in front of the muffler?

And it also very hard to keep your wheels clean when you do smoke with that set up.. truck me I am there.

I am guessing it's a remote controlled cut out.

Just a heads up on replacement filters for the 6637.Fleetfilters.com has em for 30 bucks compared to 55 bucks at Napa. Part no.546637 at F.F

The ability of an air filter to protect your engine is measured in accordance with testing procedure ISO-5011. The "genuine" Motorcraft FA-1750 (Ford P/N 2U2Z-9601-AA) has been tested to this standard but I can't find any evidence that other third party "look alike" replacement paper filters that "cross reference" to the Motorcraft FA-1750 have been tested using the ISO-5011 procedure or for that matter that they've been tested at all.

Keep in mind that over the years Ford has continuously updated and improved their stock filter element. For example the 2002 owner's manual for the F-350 specifies the FA-1680 element and then later this was updated to the FA-1720 element which has filter pleats about double the depth of the previous FA-1680 element and then additional improvements resulted in the latest FA-1750 element shown below.

The FA-1750 element is 7.3"x13.4" and it has pleats 3.3" deep. As you can see below air flows into the pleat openings at the top and then down into the deep "V" shaped pleats and out their sides. This greatly increases the overall effective filtering area.

The surface of the FA-1750 element has a kind of "waxy" feel and as I previously mentioned this distinguishing feature as compared to a plain dry white paper element is important for improved "Dirt Filtering Efficiency" of "invisible" particulate matter with very small um diameters.

A dry paper element filters on a "go or no go" basis where dirt particles that are larger than the "openings" in the filter media are trapped while particles that are smaller than the openings can pass right through. For a treated or impregnated paper element with the same size "openings" in the filter media many of the smaller diameter particles stick to the surface and don't pass through the element resulting in improved "Dirt Filtering Efficiency" of "invisible" particulate matter with very small um diameters.

The next time someone changes their FA-1750 element please take to time to count the number of pleats and post the results here or send me a PM because I want to calculate its effective filtering area.

https://h1.ripway.com/ernesteugene/D...motorcraft.jpg

That's a "US Gear exhaust brake" and it's mounted where the CAT converter used to be on my old early 99 F350. The down pipe, muffler, and tailpipe are from my Banks "stinger kit" which was the only HP improvement route available in the early 99 time frame.

Fellas,
I just bought a used 05 PSD 4x4 with 112,000 miles on it. It has an edge chip and magnum force air filter, i think its similar to a K&N filter. You just take it out and clean it. Are yall familar with the magnum force airfilter? Know anything about this brand? Any input would be greatly apprecitated , thanks

AFE made the Magnum Force intakes. It's better than a K&N, but not quite as good on the filtration percentages as S&B I believe. Just keep it clean and you should be fine.

Magnum Force vs Stock
 

How well does the magnum force airfilter compare to the stock filter that comes with the truck? Would you switch back to the stock filter? Again, I bought the truck used with this filter & don't have the original. Thanks man

No, don't swap back. If you end up wanting to change, go with the S&B or the 6637. The guys will be along to tell you there experiences...

One more question, sorry its off the subject. Why does everyone let theire diesel trucks idle? I notice a lot of the old timers do this, just let her sit there and idle. I see this a lot in the construction business. Just curious, thanks