K & N

WB9K

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tditom said:
I can speak from personal experience that an oiled filter (Amsoil, in my case) had no perceptable change on performance.

I did need to replace my MAF within 50 K miles of beginning of use, tho. :eek: Needless to say, I have never gone back to an oiled filter.

WB9K- I see you are near Detroit. I can make you a good deal on my Amsoil oil-foam filter, if you want one for your Jetta. I think most folks would agree that it is the equal to the K&N. PM me if interested.
Tom,
If you look at the links I posted in last week's thread, you'll see that the worst filtration in BOTH of the tests was by oiled foam filters (one test used Amsoil, the other used HKS). WAY worse than K&N. The testers were surprised by this, and so was I. Further, while the K&N filters did pass more debris than paper, it was a lot closer than I think most here would expect. It was for me. So, I think I'll pass on that Amsoil filter.

I'm in Walled Lake. If you need a Vag-Com scan, let me know, I have one with the Key USB interface.

dh
 

WB9K

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Drivbiwire said:
What is there to add, Considering how easy it is to just drop in the K&N, it comes straight from the package "Properly oiled" by K&N...Then when the filter is checked/replaced this is what you find...What is it that you want to know that isn't already "smack you in the face" obvious?

The filter integrity was like new, other than the coating of dust on the "Un-filtered side" and the dust that was puring thru the element.

K&N claims they outflow other filters...I tend to agree, the problem is that they tend to flow a lot more than just air.

DB
All I'm saying about your OP DB, is that you have absolutely no idea what was done to that car prior to the day you saw it and therefore cannot prove that the K&N--or anything else for that matter--is the root of the problem. You simply do not know.

dh
 

WB9K

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Matthew_S said:
It will take some real evidence before I believe this. Dyno evidence shows this doesn't happen and the fuel economy of my car was not effected when I replaced the K&N that came with my car with a MANN.

One thing we do know to be a fact is that the K&N does not filter as well as OEM. Considering how delicate the MAF is, that can't do any good. I agree that some of the K&N hating that goes on here is overblown but that doesn't mean they are not a waste of time.
When I did the change on the Buick, I had a 75-mile commute (each way), about 95% at 55 to 70 mph. After a month or two I changed out the paper filter (it was almost new, I had just bought the car) and dropped in the K&N. My mileage went from ~24-25 to ~26-27. OK, that's more like 7% than 10%, but still easily measureable. I didn't concurrently become conscious of tire pressure, driving style, or anything like that. All else was equal to the best of my abilities. Short of a notarized affadavit, I don't know what else I can do to convince you that I observed this. I have gearhead friends who have reported very similar results with their road vehicles, and also improved 1/4 mile times with K&Ns on their hot rods.

I think it's important to note that the greatest gains seem to be at highway speeds. This would make at least nominal sense because this is when airflow demands would be greatest for extended periods. As far as turbos go, I've never done anything like a real before and after test in a car with a turbo. Maybe that makes a difference. Come to think of it, the one car I did put a K&N in that seemed to make no difference at all (based on more casual observation) was a Volvo 740 wagon (4-cyl gas turbo). Hmmmmm.......

dh
 

Matthew_S

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Well, I was refering specifically to TDI's and you are talking about a Buick. I know there is dyno evidence showing an improvement on many cars but here we aren't talking about many cars, we are talking about TDI's.
 

rdkern

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WB9K said:
When I did the change on the Buick, I had a 75-mile commute (each way), about 95% at 55 to 70 mph. After a month or two I changed out the paper filter (it was almost new, I had just bought the car) and dropped in the K&N. My mileage went from ~24-25 to ~26-27. OK, that's more like 7% than 10%, but still easily measureable. I didn't concurrently become conscious of tire pressure, driving style, or anything like that.
What time of year was this? The 1-2 months on one, then a few months on the other might just be winterized/summer fuel.

You must have had to fill that thing up every other day or so. That must get old.
 

auto_tech

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Has anyone tried one of those "Tornado" devices that install in the air intake tube somewhere? Would they work as good at giving you better mileage than just driving sensibly?
 

Dimitri16V

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So you are My. Consiencious...How often are you going to check this POS? Every 100 miles, everytime you drive thru another cars dust cloud, every other day, every other week? Did you realize that in modern race cars (FI, Turbo charged etc) that they DO NOT run these type of filters? Yup, just like the OEM they run those to protect the delicate sensors and turbo compressor blades.

An example of where you will never find a K&N...
You are wrong at that. WRC cars ran K&N style filters. For what's worth, that K&N filter was improperly seated and let dust by.
 

Dimitri16V

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keep in mind race cars use KN cone filters that are inside a housing which is connected to an air scoop. The assembly is positioned to avoid water intake mainly. Also, longevity is of no concern since race engines are only meant to last that long.
I did ran a KN on my first TDI for 45K, the MAF was ok. I agree with DBW that using them is taking a risk since overoiling the filter will contaminate the MAF. But on the other hand MAFs have been known to die from other causes too.
 

WB9K

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Matthew_S said:
Well, I was refering specifically to TDI's and you are talking about a Buick. I know there is dyno evidence showing an improvement on many cars but here we aren't talking about many cars, we are talking about TDI's.
Hi Matt,
I guess we both got a little confused in the dustup. All measureable improvements I have experienced with K&N filters have been on other cars. I assumed that things would be the same with the TDI, but I did not wait long enough before putting the filter in to actually verify it in this case. Maybe it's not at all the same, but all most people here are willing to give is anecdotal evidence and half-ass analyses like the one at the beginning of this thread.

Maybe you can tell me....what is it that makes the TDI see no difference with a high-flow air filter when so many other cars do? Diesel? Turbo? Nuances in the ECU? All of the above?

Thanks for your input.

dh
 

WB9K

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dieseldorf said:
dh, it seems like you're at the point where you've elected to run a K&N filter in your TDI. I'm certainly not going to try to talk you out of it or change your mind.

There are a couple of people here who share their positive experiences with such products. There are many here who will offer a counterpoint. This subject has been beaten senseless. I can see no reason to perpetuate the discussion and I believe there's a forum rule against it.

And with that, I'd like to say "welcome aboard" and may you get excellent service from your new TDI acquisition!

Take care.
Thanks for that, DD. Not trying to start a flame war--I hate them. Just looking for some info good enough to hang my hat on. Not easy to come by on this subject, it seems. Is there really a forum rule against debating K&N air filters? An audiophile forum I hang out on has rules against debating double blind testing on certain boards. Some topics just cause all rationale and civility to go out the window, I guess.

See you around!
dh
 

WB9K

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andreigbs said:
Maybe keeping things in perspective will help. Look at this way: the service manual says air filters should be changed at 40K miles. Just because the filter "looks" dirty doesn't mean it's time to change it at 5k. And those monkeys at Jiffy Lube shouldn't even touch it, but that's another story.

Anyways, at around 40K you pick up a brand-new OEM filter for a whopping $13, which is good for another 40K. So if your engine lasts you 250,000 miles and you don't crash the car or sell it in this time, you'll have spent $82 on just air filters.

Using the K&N filter, you have to figure in the cost of at LEAST one bad MAF caused by the oil. Sure, you could have the MAF go out using the stock paper one as well. But how much more at risk is the MAF with more dust and dirt particles slamming into it? More air flow means less resistance, i.e. filtration.

So you pay the $45 for the K&N, and you buy the $12 recharge kit which is good for about 2-3 uses, tops. Except that to keep the filtration at the best level it can be for the K&N, it needs to be cleaned and reoiled more often than 40K miles. Otherwise you're just letting in all kinds of debris into your engine and turbo, which is like sand in private parts, as DB wittily pointed out.

Not only does the K&N filter not seal perfectly well, unlike the OEM filters which are meant for one-time crush foam seal, but you also spend more on cleaning and recharging, not considering the down-time while you wash it, dry it, oil it and replace it. Add to that poorer filtration at the cost of more flow, which your turbo more than compensates for btw, and you've got an expensive oily mess that will only cause problems sooner or later.

Why chance it? For the 1hp it adds or 5 lbs/ft of torque you just swear you can feel? Turbos are anywhere from $500 and up, MAFs from $120 and up. Why spend $45+$12= $57 for an extra factor to worry about?

Run OEM, change every 40K unless you live in AZ, keep your money for other things. My 2 pennies' worth, anyway.
Andre,
This is one of the most persuasive posts I've read on the subject here yet. I don't agree with 100% of what you said here, but I'm not going to nitpick. FWIW, I have not decided for sure to keep the K&N or not. The only reason I use them in the first place is to increase mileage. They've historically served me very well in that regard and I've experienced no ill effects (that I know of, anyway). I'm just trying to get input from the con-K&N folks that's based on more than hunches, experiences with improperly maintained filters, etc.. Thanks for posting.

dh
 

WB9K

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rdkern said:
What time of year was this? The 1-2 months on one, then a few months on the other might just be winterized/summer fuel.

You must have had to fill that thing up every other day or so. That must get old.
This was late fall, but I've seen others get similar results within just a couple of days on long trips in the summer. Good point though, those are the kinds of holes I like to see people trying to shoot into test data.

The commute and the fuel bills got very old. As soon as the lease ran out on that place, we moved a lot closer to my workplace. A very transitional period.

dh
 

supton

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dh, the TDI turbo is computer controlled. As the filter starts to plug up, the computer just increases the signal to the turbo to achieve the boost level. Since the turbo's energy comes from the waste energy in the exhaust, there is very little, if any, power loss as the filter plugs up. This is not true of a NA motor; a NA motor cannot get more air into the motor, only less fuel, as the filter plugs up.
 

Souzafone

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There's a reason why this is in 101. It's meant as a learning experience for people looking for info. If it were presented as a question or debate it would have been in the performance or mpg forums. The statements made as fact here were proven at least 5 years ago to the satisfaction of the same people who are being questioned now. Interesting to look at those old posts and see that the folks who were pro K&N are no longer active. I'm old enough to remember when K&N got their start making filters for dirt bikes and dune buggies. The thing that was great about them then was they would work on any modified machine because they attached directly to the carburetor, without the need of an airbox. Crash your motocrosser and need a new airbox? Just get a K&N. To me they have have always been seen as a cheap universal alternative ot O.E.
 

WB9K

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Drivbiwire said:
Please explain how this appies to an engine that has every gram of air measured by the MAF sensor, then the air is pumped into the engine.
More air available to pump into the engine is more air--pretty simple actually, MAF or not.

Drivbiwire said:
The airflow into the motor is nearly perfectly controlled, OEM air filters have virtually NO RESTRICTION.
Perfectly controlled? No system is perfect, especially one that has to meet such dynamic needs as this one. Since OEM filters have virtually no restriction, do you then retract your other statement in which you agreed that K&N filters flow better than paper (at the price of filtration)?

Drivbiwire said:
Regardless of what the filter is the ECU reads ACTUAL AIR FLOW, commands the turbo to increase or decrease air flow which is already corrected for pressure and temperature variations. The ECU then meters the proper amount of fuel for that corrected flow data...Translated whether you have NO filter or 10 filters the power output remains CONSTANT.
Such hyperbole. You don't really believe the ECU and turbo could magically overcome the effects of TEN paper filters in a row, do you?

Drivbiwire said:
All you have done so far is vomited "Snake Oil explanations" of "Why" an aftermarket should work...sounds great if you have no idea how an engine actually works or is controlled to meet emissions and generate specified power output.
Actually, I've shared the carefully measured, very real FE gains experienced by myself and others I know. Power gains are harder to prove without a Dyno handy, so that is less reliable I'll grant you--I've made no attempt to measure that. Actually, I have a pretty good idea of how an engine works, just not much experience with turbos or diesels.


Drivbiwire said:
That or the K&N type filters CANNOT MEET THE STRINGENT FILTRATION SPECIFICATIONS OF 10-15 MICRONS AT 98% EFFICIENCY while providing air restriction of no more than 15"WC new...AND have a 40,000 mile service life without exceeding 25"WC...Got news for you K&N on their best day can't meet ANY OF THE ABOVE REQUIREMENTS.
Since you so confidently told us all here just a week ago that there are cars out there drawing 400 Amps of battery current the second you put the key in, without even cranking the engine :)eek: ), I would like to know where these numbers come from so I can verify them for myself. Besides that, even if the K&Ns did pass those tests (and I don't know if they can or not), the two reasons I've given are more than enough to keep them from EVER being considered for stock parts.

Drivbiwire said:
So you drive down a dusty road, filter is trashed from dust...How do are you supposed to know? The filter will never be "Restricted" instead it just drops in filtering efficiency thus resulting in the amount of dirt passing thru it!
Now you're just getting silly here. The occasional dirt road or dustup is one thing. Day after day on contruction sites in west Texas is quite another. I get parts sent to me from all over the Americas and Asia all the time. I know the difference. Oh, BTW, filtering efficiency goes up as a filter clogs, not down. That's true for any filter.

Drivbiwire said:
So you are My. Consiencious...How often are you going to check this POS? Every 100 miles, everytime you drive thru another cars dust cloud, every other day, every other week? Did you realize that in modern race cars (FI, Turbo charged etc) that they DO NOT run these type of filters? Yup, just like the OEM they run those to protect the delicate sensors and turbo compressor blades.
It's pretty easy to check the MAF. I'll probably look at it damn near every time I pop the hood. I didn't realize turbos were a prerequisite for "modern" race cars. I guess all the racing guys I've known running K&Ns were using antique FI setups.

Here's the thing: you started this thread with photos from a car you worked on recently, the history of which you know absolutely nothing about. You've taken two dots and drawn a straight line between them and submitted that as proof that a certain filter type is totally without merit. If I tried to report like that in my capacity as a QA engineer I'd get my ass kicked up one side of the room and back down the other, and rightfully so. Your evidence here is bogus or at the very least woefully inadequate, period. At least two other veteran members of this forum have chimed in to say pretty much the same thing. You might be a decent mechanic. I'm sure you can change timing belts with the best of them, but between the utter falsehoods you put out there in that battery thread last week and this jive attempt at engineering or whatever you want to call it, I have a hard time putting much stock in anything you have to say.

dh
 

Matthew_S

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VFchicago88 said:
I agree with dimitri. I hate K&N, and would never recommend them, but I strongly believe this example is from a bad seal. K&N seals suck, you have to use the foam and grease they supply with the kit or whatever.

90 percent of the time, im sure people arent using these. I just dont believe THAT much dust would be in the track from a nicely sealed K&N.

Trust me, i cant stand them, and the people who defend them, and I would never use them or suggest them in a road car.
X2

There is no way, no how that this example was cause by an undamaged, properly installed and oiled K&N filter. Either the foam gasket wasn't used or the dirt was from a previously improperly installed filter.


WB9K said:
Maybe you can tell me....what is it that makes the TDI see no difference with a high-flow air filter when so many other cars do? Diesel? Turbo? Nuances in the ECU? All of the above?
Apparently TDI engines already have such an abundance of air that increasing the flow slightly makes no difference.
 

WB9K

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supton said:
dh, the TDI turbo is computer controlled. As the filter starts to plug up, the computer just increases the signal to the turbo to achieve the boost level. Since the turbo's energy comes from the waste energy in the exhaust, there is very little, if any, power loss as the filter plugs up. This is not true of a NA motor; a NA motor cannot get more air into the motor, only less fuel, as the filter plugs up.
NA=?? Non-turbo I get, just don't know the acronym. Here's what doesn't make sense to me: the turbo can only cram as much air into the intake as it can get from the outside. How can it be that the flow upstream of the turbo makes no difference at all?

dh
 

icecap

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K&n

Souzafone said:
There's a reason why this is in 101. It's meant as a learning experience for people looking for info. If it were presented as a question or debate it would have been in the performance or mpg forums. The statements made as fact here were proven at least 5 years ago to the satisfaction of the same people who are being questioned now. Interesting to look at those old posts and see that the folks who were pro K&N are no longer active. I'm old enough to remember when K&N got their start making filters for dirt bikes and dune buggies. The thing that was great about them then was they would work on any modified machine because they attached directly to the carburetor, without the need of an airbox. Crash your motocrosser and need a new airbox? Just get a K&N. To me they have have always been seen as a cheap universal alternative ot O.E.
This is an amusing topic pro and con as I'm sure that there are a great number of people who would promote Amway products with their last breath when there are better, cheaper and more effective alternatives. The whole improved airflow pitch is a joke, especially in the case of a gasoline engine which requires a throttled air intake to maintain the correct air fuel ratio. If there is a benefit to increased aiflow it would only make a difference at wide open throttle since most of the time the engine is actually running with a vacuum in the intake manifold. How much of a persons driving is at WOT unless they are a total nut bar? Having worked with large industrial diesels for decades and air filters that cost $300 to $400, air restriction gauges or filter indicators are used to monitor air filters performance and most economicaly utilize the filter life. The actual filter restriction required to make a noticeable reduction in performance is significant.
 
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supton

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Think about it this way: at 2k, say 50% output, let's say that to make the required 5psi of boost that the VNT angle is say 45 degrees (zero being no boost, 90 is full angle). Air flow restriction goes up, so the VNT angle goes up, and the turbo sucks harder. Now, if the turbo was powered by a belt, ala supercharger, sure, efficency loss. The power to run the compressor has to come from somewhere.

Maybe with a new filter, it would take 1hp of "suck" to flow enough air for that 50hp output (1hp to spin the turbo); and now it takes 5hp to suck that air past a dirty filter. But since 30+% of the available energy is blowing out of the exhaust at any given time, it doesn't matter. Well, at some point it'll take too much, and then sure, new filter time. But certainly not "1psi drop across the filter is 5% hp loss" or somesuch.

NA = Normally Aspirated.
 

whitedog

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By the by, old chaps, I just performed a search for " K&N " and searched for titles only.

No results.

The search engine only sees two letters and ignores the & so it comes up with zero results.:(
 

WB9K

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supton said:
Think about it this way: at 2k, say 50% output, let's say that to make the required 5psi of boost that the VNT angle is say 45 degrees (zero being no boost, 90 is full angle). Air flow restriction goes up, so the VNT angle goes up, and the turbo sucks harder. Now, if the turbo was powered by a belt, ala supercharger, sure, efficency loss. The power to run the compressor has to come from somewhere.

Maybe with a new filter, it would take 1hp of "suck" to flow enough air for that 50hp output (1hp to spin the turbo); and now it takes 5hp to suck that air past a dirty filter. But since 30+% of the available energy is blowing out of the exhaust at any given time, it doesn't matter. Well, at some point it'll take too much, and then sure, new filter time. But certainly not "1psi drop across the filter is 5% hp loss" or somesuch.

NA = Normally Aspirated.
Between you and a couple of others, I'm getting a picture in my head that makes sense to me. It seems to be consensus that with the stock setup, the available airflow is already more than adequate for these little engines. (I would guess this is a function of the engine's small size more than anything else). This would probably be the case even without the turbo, but the turbo just makes it that much more so.

I suspect most folks here would agree with that. Yes?

dh
 

supton

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I believe so.

Others: what setup do the 150hp euro TDI's run on the intake side? IIRC, wasn't it the same air filter and airbox and all?
 

alphaseinor

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I'll throw my hat in here... all of this is IMHO except from the evidence in the following paragraph...

I log all of the cars I service, what was done, when it was done, what was recommended to the customer, and what they refused to have done. I have had ten customers cars with MAF failures in the last year, all but one were running a K&N filter, properly installed... the other was an improperly installed FRAM branded air filter. I have had 123 (one hundred twenty three) cars with misc paper filters (most are return customers, MANN is the filter of choice) so that's a very small percentage of failed MAF sensors under the paper category. I had a total of 12 (twelve cars) come through my shop with K&Ns. That's three good MAFs out of twelve using K&N filters, which is pretty damning evidence. Want the VIN numbers, and dates of service??? Or should I come back when the K&N filters have a statistically significant number of failures?

You also need to realize that I come from a high performance side of GM aftermarket. K&N filters can work in GM cars, mainly because of the type of technology they use in their MAFs. GMs use hotwire and coldwire technologies, where almost all of the german manufacturers use a membrane type. The hotwire will still get gunk on it (as a matter of fact, if you go into any reflash forums, this shows up as a common problem when someone changes the MAF tables for KR when the original problem was a hotwire that was gunked up... no need for a MAF table update... starts screwing with the data calcs from the VE tables).

The coldwire is a more modern upgrade, but as far as I can tell, no one has complained about K&N with LS1 and similar engines. So the K&N may actually work with this setup, albeit may still have frequecy variations from a coating of oil.

The membrane type have a temperature sensor literally printed using a thin film semiconductor process.

The last time I checked most semiconductors are made in clean rooms.
Most clean rooms are not filtered by K&N...
 
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dlai

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Ok, I thought I'd add two pics from a GTG I was at a few months back. TDI with a K&N filter, "very lightly oiled" as the owner put it. Low on power, this after getting chipped. MAF was pulled from the car and this very lightly oiled filter (recharged, as K&N puts it), was dead. MAF was replaced and all power was back. Oil coats the MAF and the grit that gets by the K&N collects on the MAF, burning it out.





Reason enough not to use a K&N, unless one has deep pockets and doesn't mind replacing MAFs every so often...
 

DieselOx

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None, and it's a relief, kind of.
Has anyone bothered to log MAF-actual on their vag-com with stock v. k & n filters? Seems to me they would be identical, and should put this to rest for good. (Should be in a FAQ, if it isn't already).

[others with more appropriate knowledge could suggest the right tests to run to prove this one way or the other, if anyone was so inclined]
 

WB9K

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Diesel Ox,
Outstanding suggestion! I'll buy a paper filter and perform a test ASAP, probably this weekend. Live driving while watching the MAF readings should do it, yes? Engine block 3, I think. Any other suggestions?

As for the oily MAF, others have posted similar photos. My MAF is bone dry, but it's only been a few weeks with the K&N.

Alpha, no need for VINs or anything like that, I believe you. Those are indeed compelling numbers if the filters were in fact proper (and this is really the big question in my mind with many of the "oiled to death" claims.) The point about different MAF types is duly noted, though I kind of doubt that the film MAFs actually have semiconductors printed on them. Capacitors or wire resistors maybe, but semiconductors seem highly unlikely to me. (Ever seen a clean room? The filters are just the tip of the iceberg--those guys wear spacesuits. De-ionized air is forced from vents covering the entire ceiling through vents in the floor. The "floor" is really just a giant vent grate. WAY cleaner than any airbox, I don't care what filter you're running.)

Cheers!
dh
 
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Drivbiwire

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WB9K said:
More air available to pump into the engine is more air--pretty simple actually, MAF or not.
And there in lies your lack of understanding of how a turbo diesel engine operates or for that matter functions.

You do realize tha the MAF sensor is the PRIMARY source of control for fuel injected to the motor? You do realize that more air in the cylinder WILL NOT RESULT IN MORE POWER FOR A DIESEL ENGINE since ALL DIESEL ENGINES ALREADY HAVE EXCESS AIR DUE TO THEM BEING LEAN BURN COMBUSTION ENGINES...At idle they run as lean as 100:1 and at full load they are at 35:1 and NEVER approach 14.7:1 like gassers???

This is the same reason why you can crank your boost pressure to 100psi and the only thing that will happen is you drop in power due to backpressure. Combustion does not improve, power does not improve and effiency is unaffected.

Perfectly controlled? No system is perfect, especially one that has to meet such dynamic needs as this one. Since OEM filters have virtually no restriction, do you then retract your other statement in which you agreed that K&N filters flow better than paper (at the price of filtration)?
K&N vs OEM will NOT flow as well due to the OEM having nearly 15 times the surface area (Cold climate "A" filter). Due to the larger area this offsets the smaller media pores thus inreasing the overall flowability of the filter when compared to the K&N. OEM filters have over 12 square feet of area vs the K&N's 1 square foot... The key is that the pore size on the OEM filter is around 10-15 microns vs the K&N's 100-150 microns size. The MAF is affected by particles in the 15-20 micron range due to static attraction from airflow in the MAF sensor element channel.


Such hyperbole. You don't really believe the ECU and turbo could magically overcome the effects of TEN paper filters in a row, do you?
If you had any clue about how a "Forced induction motor worked" then you would understand this concept...this goes back to engines 101.

Turbo charger DETERMINES the volume of air at a "specified" pressure which is delivered to the engine in all regimes. The ECU reads the actual flow into the motor via the MAF sensor, corrections are applied to the detected airflow corrected for temperature and local pressure. If the ECU is not seeing the "Specified" flow for a given load (Pedal input) the ECU commands the VNT to increase boost pressure. Maps are built in to act as a check and balance to prevent overspeeding of the turbo or overboosting in the event of a sensor failure. The Maf sensor is capable of sampling at over 1000 times per second, in other words it can watch the flow reversals in the incoming airstream due to individual valves opening and closing...This ain't some Buick Bubba.


Actually, I've shared the carefully measured, very real FE gains experienced by myself and others I know. Power gains are harder to prove without a Dyno handy, so that is less reliable I'll grant you--I've made no attempt to measure that. Actually, I have a pretty good idea of how an engine works, just not much experience with turbos or diesels.
I can't tell you how many hours I have spent working with Dynos and TDI's. Just for grins one day, we removed the whole airbox and did a run. No gains whatsoever. Even with the fans pumping air into the inlet to simulate ram affect under driving conditions at 120 miles per hour, there were still no gains.

Since you so confidently told us all here just a week ago that there are cars out there drawing 400 Amps of battery current the second you put the key in, without even cranking the engine :)eek: ), I would like to know where these numbers come from so I can verify them for myself. Besides that, even if the K&Ns did pass those tests (and I don't know if they can or not), the two reasons I've given are more than enough to keep them from EVER being considered for stock parts.
Feel free to hook up a load meter on a cold morning...Report back the load on the battery before and during cranking...

You could also just add up the "Powered consumers" that are activated when the ignition switch it turned on, Take some initative and knock yourself out.


Now you're just getting silly here. The occasional dirt road or dustup is one thing. Day after day on contruction sites in west Texas is quite another. I get parts sent to me from all over the Americas and Asia all the time. I know the difference. Oh, BTW, filtering efficiency goes up as a filter clogs, not down. That's true for any filter.
Report back when you understand "tracking" as it relates to "oiled filter elements". You realize that a single pass thru a dusty area is sufficient to affect an oilded filters efficiency at stopping dirt? Once the dirt absorbs oil in a specific area the airflow simply follows the path of least resistance and dirt along with the air flows thru this formed channels.


It's pretty easy to check the MAF. I'll probably look at it damn near every time I pop the hood. I didn't realize turbos were a prerequisite for "modern" race cars. I guess all the racing guys I've known running K&Ns were using antique FI setups.
Probably were, most racing fuel injection systems do NOT use a MAF sensor since the motors do not have to meet any emissions requirements. Audi in the R10 CHOSE to meet emissions standards they imposed on themselves to demonstrate a diesel can be raced without visible smoke.

Rally cars (WRC) do not use MAF sensors, instead the ECU's utilize MAP (Manifold Air Pressure) for the primary boost control to the ECU. This is a sloppy way of controlling boost but for the purpose of simplicity it works. Other corrections are used to dial in the motor such as TPI and IAT.

Here's the thing: you started this thread with photos from a car you worked on recently, the history of which you know absolutely nothing about. You've taken two dots and drawn a straight line between them and submitted that as proof that a certain filter type is totally without merit. If I tried to report like that in my capacity as a QA engineer I'd get my ass kicked up one side of the room and back down the other, and rightfully so. Your evidence here is bogus or at the very least woefully inadequate, period. At least two other veteran members of this forum have chimed in to say pretty much the same thing. You might be a decent mechanic. I'm sure you can change timing belts with the best of them, but between the utter falsehoods you put out there in that battery thread last week and this jive attempt at engineering or whatever you want to call it, I have a hard time putting much stock in anything you have to say.
As a newbie, you may want to spend 1000/th of the time I have learngin the systems in these cars. Once you have basic understanding and stop confusing gasoline engine concepts with diesels, take the time to undertand the controls of the motors then you will begin to see why I'm not blowing smoke...

As for that other thread, I'm still waiting on somebody to come back with the total wattage of the systems powered by the battery before starting the car...Then again you still seem to think this is a Buick with a simple condensor and points ignition system...

DB

dh[/quote]
 

l1o9s7t6

Veteran Member
Joined
Apr 11, 2005
Location
Alaska
TDI
jetta, sedan 2002 blue
This is simple enough for anyone. Go down to your local parts store take a brand new K&N filter out of the box (get a panel filter) rip the plastic off and hold it up so that you are looking through the filter at the lights above your head. See the small holes that are letting light shine through......
Guess what else goes through? IF you dont believe it.......LOOK

on a side note... the dirt that goes through all those little holes. Acts like a sand blaster to your turbo vanes spining at 100K + RPM. We have a local shop that collects the turbines out of powerstrokes with K&N filters in them.
 

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
but between the utter falsehoods you put out there in that battery thread last week and this jive attempt at engineering or whatever you want to call it, I have a hard time putting much stock in anything you have to say.
Drivbiwire said:
The first priority for ANY modern car is Ah rating FIRST which DIRECTLY corresponds to the ability of the battery to Supply a minimum voltage under load for an extended period...Powering 7 glow plugs (50+30amps), ECU, Immobilizer, radio, heated seats, lights, instrument cluster, ESP computer, ABS computer, CD changer, Fan for the climate control, 30-40 engine sensors and servos, tank fuel pump.... AND all BEFORE YOU EVER HIT THE STARTER without ALLOWING the voltage to drop below 10.5 volts!
Wheres the Bull$hit? Are you telling me that none of these items are powered anytime the ignition switch is "on"?

Have you stopped or even taken the time to add up the total wattage of any of those systems?

Here is what VW has to say about the function of the battery in these cars:

Apart from starting the engine, the battery has other tasks. It acts as a buffer and also supplies electrical energy to the complete vehicle electrical system. In addition, the cyclical and capacity demands on the battery have increased due to additional safety and convenience features (electrical consumers) being installed.
Like I posted the cars systems can draw up to 400 amps BEFORE being started, this case is a worst case scenerio.
The luxury cars often have TWO battery's one 95Ah and another 35Ah to power the misc systems. They go so far as to have load shedding which kicks in at predetermined voltages in order to protect the ability for the car to start.
DB
 
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