Been looking at intakes. Was wanting to get yalls thoughts on aFe 50-1006.

I've read good things about afe intakes but I'm a bit concerned about this one because the air from the front beside radiator looks blocked.

Thanks

 

That looks like a 6637 in a housing? I have no issues with my 6637 open under the engine bay......

 

Look at your truck. There should be a large hole cut out of the fenderwell that the edge of that box would but up to. That was designed from the factory as an air intake port.

Drawing air from this location will prevent you from drawing in air heated by the engine since it's coming from between the inner and outer fender.

 

Here is what I don't understand. Why is the stock box or the Ford ais not drawing air from the fender. It looks to me that if a mod was done on stock air box to pull air out of fender also it would improve air flow. The filter looks bigger on stock vs ais so what is limiting flow on stock? Anyone heard of this type mod?

 

Two intake ports
Like this

 

Cutting a hole on the side of an AIS is a common mod, generally called a sleeved AIS. The sleeve is a foam filter from a shop vac used between the fender hole and the big 3" hole you just cut into your expensive new airbox.

I think the rule of thumb is AIS is good for up to about 350ish hp.

Stock air boxes have a bad rep for breaking clips and letting unfiltered air in. Also many aftermarket filters do not fit properly and admit dirty air. As I recall Ford went away from taking air thru the fender due to cases where ice and slush got in under certain conditions.

S&B is also a popular choice for higher hp. Not as quiet as AIS but flows better. Louder still is the 6637, but that's a decent choice too. I ran that for a few years.

 

This is one reason why:





And the photo above is only a very mild example of the icicles I've seen forming along the lowest point drip line of the bumpers and fenders of north east vehicles in the dead of winter.

It's easy to see the big hole in the side of the inner fender. But how does air get IN to that fender? Where is THAT hole, that ducts fresh outside air inside the fender so that the big hole is actually meaningful?

Well, THAT hole is at the forward most and lowest drip point of the fender, and it is less than 1/4th the size of the big hole that you see. So there are several negatives that interplay here...

1. THAT hole, the REAL hole where outside air enters the fender, is quite SMALL, compared to the big fender hole that you see. This wouldn't be so much of an issue, as there the volume of space within the fender itself serves as a "reservoir" for peak demand pulls, and the restriction of the filter is still greater than the restriction of THAT small REAL hole, however...

2. THAT hole, the REAL hole, happens to be located where icicles tend to form on the truck, because water (or snowmelt) flows down the sides of the body to the lowest points before following gravity to the ground... and just as it drips off of these lowpoints, the ambient air temperature refreezes it into an ICE DAM that can not only further restrict the small triangular REAL hole, but in severe weather can build up a frozen stalactite that can block the hole altogether.

This was reported to happen with early 99 trucks that used the fender hole exclusively for air intake, before Ford redesigned the intake with a snorkel feeding from a drip protected higher position in the front of the truck. The real lower forward fender hole would become blocked, and the non screened, thin panel peated filter (the old 1680) would get pulled upward from the center, sometimes tearing apart and getting sucked into the turbo. Terrible news. The part was redesigned within the initial model year of the Super Duty.

But that isn't the only reason why the fender well inlet created problems...

3. THAT hole, the REAL hole, is in the radial trajectory of tire flung debris... meaning that wet mud flung from the tire treads can cling to the fenderwell liner and build up as each layer dries just enough to provide a good base for the next wet layer to adhere to. Like building an adobe hut upside down. That hanging hut of adobe can also block the real hole, starving the truck for air, if that is the ONLY source for air.

As a supplemental source, the mudcaking problem no big deal, but this answer is intended to address some of the reasons why the fender hole was abandoned as the sole source of air for the stock intake... and is not intended to condemn the use of the hole by enthusiasts as a supplemental source of air in tandem with less vulnerable sources, such as the stock snorkel.

Those who don't live in the snow or run their truck through muddy irrigation ditches on the edges of farm fields may have a hard time visualizing these issues, but the challenge of OEMs it to design a part that works well in ALL applications and climates. And the less obvious "climates" are localized microclimates that have nothing to do with where one lives, but more on the immediate conditions presented in operation... illustrated by...

4. THAT hole, the REAL hole, is located in the "storm region" of the wheel well. Even if the sun is shining brightly outside, when the vehicle is driving at highway speeds on wet freeways, a typhoon like microclimate is generated by the tires pinwheeling road surface water within the wheel wells, atomizing this water into a fine mist that is more easily drawn up into the intake, saturating the filter. This was another reported complaint of the early 99's that relied on the fender well inlet exclusively.

Multiply this wheel well mist by all the other cars and trucks speedboating along on the same freeway, and there is a lot misty air to be drawn up from a relatively low inlet. There is a limit to how high tire generated mist can rise before gravity yanks it back down to the ground again like rain fall, so raising the inlet scoop just a little bit higher can mean a lot dryer air, and less probability of water saturating (and thus weakening the fibers) of the air filter.

Speaking of wet roads, the current flooding in the South comes to mind, where driving a Ford means just that... fording rivers that were once roads. Which leads to..

5. THAT hole, the REAL hole, is more vulnerable to becoming blocked entirely by a water dam created when the front of the truck plows up water into a wall that exceeds the height of the actual depth of water being forded. The hole is even with the bottom tip of the fender, underneath the front marker light. As the wall of water getting pushed by the bumper rises and flows back over the top of the bumper, it can create intermittent (or sustained, depending on the depth of water) blockages, which again can create a restriction strong enough to collapse some types of flat panel pleated air filters.

In conclusion, the foregoing are just some of the reasons why the STOCK air box stopped using the fender well inlet within the first model year of the Super Duty being introduced. However, these reasons should not preclude you from adding the fender well inlet as a supplemental source of air to whatever air box you choose. Probably not a good idea to use the fenderwell as an exclusive source though. This advice does not apply to vehicles in general, just this specific generation of Super Duties as built.

 

Thanks for your great reply. After looking around on the Internet found this. Would it be a stupid idea to take my square stock box and cut a hole in the side and rigg some type of tubing?

 

Btw I have a k&n air filter now that's atleast 10 years old. 😨

 

Both your original square stock box, and your 10 year old K&N flat panel filter, are not recommended. It doesn't matter whether or not you cut a hole in your square stock box, as the stock box itself is not a good idea, due to the way the lid fails to seal on the clean side of the filter.

The idea of an air filter is to do exactly that, FILTER air, and neither the stock box nor the flat panel K&N filter have proven to do the job they are installed for very well. I've had them both, I've tested them both, and I've tossed them both, in very short order (within weeks, not months).

If you've been running a stock box with a flat panel K&N for a decade, then you might want to pull your entire air inlet tube off, on both sides of the CCV inlet, and inspect your turbo compressor blades for wear on the edges. Also run an oil analysis.

 

Ya know, I'm getting tired of people bashing the K&N panel filter. There is nothing wrong with it. It likely filters practically the same as any other aftermarket washable cotton filter, including AFE and S&B.

I had one on my truck for about a year (It was on it when I bought it.) I had no dusting. I have since switched to an S&B, but for air flow needs of my Stage 1 sticks and WW2. If I had stayed with stock sticks, the K&N would have been just fine, and would still be in the truck.

Now, I do realize there is an issue with MANY aftermarket panel filters sealing to the airbox. BUT, even the factory filter doesn't always seal properly. It is a design flaw with the FORD airbox, not the K&N (or any other) filter. I resolved it by using RTV to "glue" the filter to the airbox lid. That seals it perfect. No chance of unfiltered air, even if the airbox clips fail.

 

Most people get it when the word "Google" is used instead of saying searching on line; when the word "Xerox" is used instead of saying making photo copies; when the word "Kleenex" is used instead of saying facial tissue; when the word "Clorox" is used instead of saying household bleach; etc. etc..

The brand names of product innovators and market leaders are often spoken to describe, in short hand, the products themselves, regardless of the actual brand of the specific iteration of said product.

Such is the case with my use of the brand "K&N", which was spoken in short hand instead of saying "oiled cotton gauze filter media captured in a pleated mesh screen". This does not constitute brand bashing. If anything, it continues to herald K&N as the market leader in the category... the namesake of all similarly constructed filter media.

Therefore, it is no revelation that the K&N filter "likely filters practically the same as any other aftermarket washable cotton filter, including AFE and S&B." I included the S&B equivalent flat panel filter in my air filter testing, as well as other brands of oiled fabric and cotton gauze filters (Volant, etc).

In fact, here are my own personal K&N and S&B filters that I used for testing, sitting side by side for comparison:





So, no, this isn't about bagging on K&N. It is about the suitability, reliability, and filtering performance of this TYPE of filter in the 99-03 7.3L diesel application in a stock airbox. Again, not recommended.

 

So, wait, am I reading this as you think ALL washable cotton filters = death to diesels?

If that's the case, well, I don't what else to say, as that is a ridiculous position, proven wrong by millions of users

If, instead, you are just opposed to the flat panel, stock replacement type ones, then again, there is nothing wrong with any of the aforementioned filters.The problem is with the FORD airbox. A little RTV around the edge fixes the issue. Yeah, its a little inconvenient, but it is effective.

If your mods don't require the enhanced airflow of complete C.A.I. system, then a higher flowing panel type is a good budget alternative. Before I swapped injectors, I put a stock (motorcraft) paper filter in while I waited for the K&N to dry (it was the middle of winter and I had just washed it.) When I had the chip at anything higher then stock, it would smoke noticeably. When the K&N was reinstalled, the smoke was considerably reduced.

 

What are you reading? The discussion and context was flat panel. The description and application stated stock air box. The only type of filter that can be fitted to a stock air box is a flat panel. Even a photo, worth a thousand words, was included to clarify unequivocally EXACTLY what is being described. Why are you attempting to expand the meaning to something incredulous?




There is no doubt, nor debate here, that a clean K&N style flat panel filter will flow more cfm than the original stock 1680 flat panel pleated paper filter of 1.5" depth when tested at 25 inches water column on a calibrated flow bench fitted with a stock air box assembly oriented in the same direction. So will the S&B, etc.

The problem is, K&N, who was invited to participate in this testing, and who initially was going to provide an evaluation copy of their then brand new, just introduced FIPK (at the time I was testing entire CAI systems as well as flat panel replacements), stated that the filtering efficiency with the K&N filter improves when their filter gets dirtier. By efficiency, K&N was referring to their filter's ability to filter... not flow. After all, that is why we install filters right? Not to flow more air, but to filter the air being flowed.

Even K&N admits that their filter doesn't filter as well until it gets dirty. In other words, the dirt that gets embedded in their filter helps block more dirt from getting through the filter, and K&N reiterates that this is a good thing, by design. So what does that say about the filtration ability of the clean filter out of the box? It needs to be dirty to filter more "efficiently". But the same dirt that restricts more dirt, also restricts more air, which naturally, and in some cases substantially, diminishes the flow advantage that the clean K&N had over a quality pleated paper stock filter.

So the key metric in filtration is dirt holding capacity prior to restriction. This is the meeting of the matrix where service life, service cost, filtration effectiveness, and meeting the air ingestion needs to support combustion all come together in balance. If the efficiency curve of the K&N style filter is steep, where it flows really great when it isn't filtering that well, and then begins to filter better while flowing poorly within a shorter period of time, requiring more frequent maintenance... then maybe that isn't such a good filter for daily driven work truck applications.

In racing, where the engine is serviced prior to every run, or in the hands of an enthusiast who opens the hood as often as the driver's door, some of the issues in the matrix are moot points. But for folks who just want their truck to work with minimal fuss and a reasonable maintenance schedule, finding a filter with a higher dirt holding capacity prior to restriction, that at the same time is effective at preventing dusting in all driving conditions and operating temperatures, from the time the filter is new out of the box to the time it needs replacement, there are some better choices than a flat panel K&N style filter with only 1 inch pleat depth and fewer pleats across to capture the dirt.


I'm not arguing with your personal experience enjoying your K&N style filter. I'm not debating that a clean K&N style filter will flow more air initially. And we agree also that the K&N flat panel filter is not well suited to the Ford stock airbox. Here is another example of the incompatibility between the two, that has nothing to do with the perimeter lid seal:





In the photo above, we see the damage to the filter screen from the panel retention post that is incorporated into the 2001-2003 stock airbox lids (and earlier trucks retrofitted under Ford's airbox replacement TSB program at the time). This damage is done to this brand new filter only after three installation cycles (you can see three different indentations) all done within the relatively short testing period.

For a filter that needs to be washed, dried, and reoiled repeatedly throughout it's service life in order to maintain it's higher rate of flow (at the cost of filtration efficiency), I cannot see many folks wanting to scrap the RTV off the perimeters of both the filter gasket and the lid flange, only to regoop it up again and let it cure before being able to use the truck. I don't think most people have time for what you describe as a "little inconvenience". I'd rather just pop in a known good filter and go right away.

Or better yet, buy a replacement airbox and filter assembly which has the highest dirt holding capacity prior to restriction measured in a factory approved filter... the AIS.

 

I apologize for chiming in without reading everything here, but I know Y2KW57 is an expert on this topic, and I read enough on both sides to get the gist of what's taking place.

Brian Howie wants more air on-the-cheap, and carguy3j is defending his choices - based on his observations and experience.

I also have a background in filtration, but mine was in a denser fluid - water. With water, filtration differences are far more obvious. So... I never needed a laboratory to learn what works and what doesn't - just pressure gauges before and after the filtration. Between the very poor design of the stock box and the limited available space to allow a turbo on big cubes to breathe, I just say "Stock bad, many aftermarket products good - with AIS at the top for stock sticks/turbo". As for K&N vs. other brands... if it fits in the stock box, they all "suck".