In the years I ran my dyno business, we replaced the original air filters with direct K&N replacements at LEAST one hundred times in back to back comparison tests with the original factory filter. In ALL BUT ONE case, the K&N filters made LESS power than the stock filter. I remember the only car that showed a power improvement was the Volkswagon Corrado with the supercharger. I was never impressed with these filters. It goes to show that measuring pressure drops is NOT the same as measuring power. K&N filters have measured lower pressure drops than factory filters, but this does not translate into more power. By the way, there are a lot of other examples where improved air flow measurements or pressure drops actually reduced power.
K&N filters are Not for Me
- Thread starter OriginHacker21
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i would like to know what the intial restriction of these filters are...i use motorcraft they are listed at 1.5 mmh20 initial...i the air filter study it showed purolator the standard one at 1.7 mmh2o..k&n tested at 1.3mmh20
and all day long I have to put up with "dude, can you look me up a KN intake for my 1990 Honda crack head car." irritating! lol. and then I hand them a Pureone oil filter and they want a KN oil filter. Ug.
carock said:
"In the years I ran my dyno business, we replaced the original air filters with direct K&N replacements at LEAST one hundred times in back to back comparison tests with the original factory filter. In ALL BUT ONE case, the K&N filters made LESS power than the stock filter. I remember the only car that showed a power improvement was the Volkswagon Corrado with the supercharger. I was never impressed with these filters. It goes to show that measuring pressure drops is NOT the same as measuring power. K&N filters have measured lower pressure drops than factory filters, but this does not translate into more power. By the way, there are a lot of other examples where improved air flow measurements or pressure drops actually reduced power."
I've been following the K&N air filter debate for two or three years on this and on 3 Ford Ranger forums and a Subaru Forester forum, with great interest. I think that this is the best argument I've seen for the claim that the K&N does not increase power, assuming that what he says is true, and I have no reason to believe that it isn't. That said, I'd really appreciate it carock if you would elaborate on what you said. Was it a truly professional shop, with a quality dyno? Were the tests run under controlled conditions? For example, run on dyno with paper filter, immediately switch to K&N, and immediately run on dyno again? No gain in EITHER hp or torque? Do you know if other dyno shops also rarely or never measured any power gain, and whether any dyno shops DID measure a power gain?
I'm running the K&N in two 2003 vehicles. I've become increasingly sceptical the past year or so of the value and advisability of doing so. Besides your post carock, I've been very interested in the often-posted link on what appears to be an excellent independent study of the air flow of the K&N and other types of air filters, a study that is not at all favorable toward the K&N. I'm about ready to switch back to paper and your post might just have tipped me over that edge.
"In the years I ran my dyno business, we replaced the original air filters with direct K&N replacements at LEAST one hundred times in back to back comparison tests with the original factory filter. In ALL BUT ONE case, the K&N filters made LESS power than the stock filter. I remember the only car that showed a power improvement was the Volkswagon Corrado with the supercharger. I was never impressed with these filters. It goes to show that measuring pressure drops is NOT the same as measuring power. K&N filters have measured lower pressure drops than factory filters, but this does not translate into more power. By the way, there are a lot of other examples where improved air flow measurements or pressure drops actually reduced power."
I've been following the K&N air filter debate for two or three years on this and on 3 Ford Ranger forums and a Subaru Forester forum, with great interest. I think that this is the best argument I've seen for the claim that the K&N does not increase power, assuming that what he says is true, and I have no reason to believe that it isn't. That said, I'd really appreciate it carock if you would elaborate on what you said. Was it a truly professional shop, with a quality dyno? Were the tests run under controlled conditions? For example, run on dyno with paper filter, immediately switch to K&N, and immediately run on dyno again? No gain in EITHER hp or torque? Do you know if other dyno shops also rarely or never measured any power gain, and whether any dyno shops DID measure a power gain?
I'm running the K&N in two 2003 vehicles. I've become increasingly sceptical the past year or so of the value and advisability of doing so. Besides your post carock, I've been very interested in the often-posted link on what appears to be an excellent independent study of the air flow of the K&N and other types of air filters, a study that is not at all favorable toward the K&N. I'm about ready to switch back to paper and your post might just have tipped me over that edge.
What stopped me from using my K&N was the fact that I saw no dust particles after 5k of driving. Whereas now with a paper after 2k of driving there is dust/dirt in the media that I can blow off.
Where did all that go with the K&N?
Where did all that go with the K&N?
During one of well over a dozen dyno runs, which were being done in conjunction with designing a new exhaust system on my supercharged Jaguar 4.2 XKR, I decided to remove the Purolater pleated "paper" panel air filter, and after carefully vacuuming out the entire air intake system, did a couple of pulls with no air filter element at all in the system.
The results: not even one horsepower or foot pound more than the previous two pulls or the following two pulls with the filter element back in the system. The tracings of the power curves were just identical with different colors of ink superimposed on top of each other.
That was enough to convince me that there was nothing to gain from using any "Free Flow" air filter EXCEPT a lot more dirt in the engine and the oil.
The results: not even one horsepower or foot pound more than the previous two pulls or the following two pulls with the filter element back in the system. The tracings of the power curves were just identical with different colors of ink superimposed on top of each other.
That was enough to convince me that there was nothing to gain from using any "Free Flow" air filter EXCEPT a lot more dirt in the engine and the oil.
Wouldn't that dust be caught by the oil and kept on the outside of the filter? K&N states the dust caught on the filter helps filtering. The more durt/dust the better the filter works.
I have used a K&N on my Accord for 160.000 kms with no problem at all.
I am using one now in my S2000, but thats to short of a time to make defenite statements.
I agree about the re-oiling, its not easy but when you read the manual (what?.. a manual?..
Just figured I would add a little fuel to the fire
Pontica is using K&N filters as OEM on their new pontiac.
http://www.leftlanenews.com/2006/04/03/2007-pontiac-g6-gxp-coupe-concept-unveiled/
Pontica is using K&N filters as OEM on their new pontiac.
http://www.leftlanenews.com/2006/04/03/2007-pontiac-g6-gxp-coupe-concept-unveiled/
Dodge has been offering the K&N style filters as part of an upgraded intake kit for some of their vehicles for a few years now.
http://www.mopar.com/m_perf_subcat2Check.jsp?SubSubSubGrpID=748&dummy8=1144193492690
Ford Racing also offers this style of filter as a drop in replacement for several of their vehicles.
http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=7648
If you look at the title of the article, you'll notice that this is a CONCEPT. I would bet big money that GM is not going to actually produce this car with a factory-installed K&N filter. I don't believe any manufacturer would produce a vehicle with a reusable oiled cotton gauze filter like K&N's. That makes the general maintenance harder on the customer. What consumer (besides us enthusiasts) want to mess with cleaning and re-oiling a air filter vs. just replacing it with a new one?
GM has a lot of concepts. by the time it hits the public it's like watered down kool-aid. I don't get all excited anymore when I see GM concepts.
And don't forget, the general only covers cars for 3yrs or 36K miles which ever comes first. Where as Toyota and other folks have a 5yr/60K type warranty.
And don't forget, the general only covers cars for 3yrs or 36K miles which ever comes first. Where as Toyota and other folks have a 5yr/60K type warranty.
You are exactly right. Maybe I wasn't doing it right but I held my K&N Air filter up to the light and looked for little particles of dust (very visible on a paper air filter) - and I didn't see one spec of dust after 5k. Maybe it just blends in ... lol but whatever. I haven't thrown it away. May wash it and run it after I get these Fram Toughguards used up.
(Above post): Shows you how much trust GM has in their products. I just passed 36,000 in my car and it is way too early for a warranty to end on ANY car...
Funny, I've gone waaayyy past the Nippon's 5yr./60K mark in my "unreliable" GM and NEVER needed any stinking warranty. Man, I must be really lucky. I guess I should go dump a couple of grand on the Mega lottery, huh??
The dyno tests I performed in my shop ( Rockwell Motorsports, San Jose, CA) were done as scientifically as possible.We ran the tests back to back, no other changes. We even switched the filters back to stock and got the same results. The tests performed on the chassis dyno were amazingly accurate and repeatable as long as the horsepower did not exceed about 160 hp. We would get repeatable runs within 1/2 horsepower all the time. K&N filters just do not make more power than stock filters. K&N got a good name when David Vizard published tests that showed they flowed better than stock filters. The ASSUMPTION was that better flow meant more power. This is simply not true. The correct theory ( I think)is that the airflow needs to be progressively accelerated into the intake valve, and air flow restrictions that speed up flow are helpful when done in the right places.
Hey dailydriver - didn't mean to come across as a GM hater. Actually, I'm a GM only buyer (I own a 2004 Pontiac Sunfire). I plan on taking it to 400,000 miles so...
My next car will be GM as well. Haven't had any problems with my car either.
It would be nice to see GM go to 60k or so as that says "We believe in our product."
In regards to above: I don't see how K&N can have better air flow. I took my STP paper filter and my K&N filter and did the "scientific" blow test with my hand on the other side. I couldn't feel any air no matter how hard I blew on the K&N. With the STP I felt air without having to blow too hard. ?
It would be nice to see GM go to 60k or so as that says "We believe in our product."
In regards to above: I don't see how K&N can have better air flow. I took my STP paper filter and my K&N filter and did the "scientific" blow test with my hand on the other side. I couldn't feel any air no matter how hard I blew on the K&N. With the STP I felt air without having to blow too hard. ?
K&N has the data to show it flows air better.
Blow test is probably just showing media difference of paper and cotton. I thought the issue was mainly whether better flow translates into more power which is seldom the case as the filter is not the restriction usually and filtration. If anything your blow test would seem to show it filters better but I don't think that's the case either
Blow test is probably just showing media difference of paper and cotton. I thought the issue was mainly whether better flow translates into more power which is seldom the case as the filter is not the restriction usually and filtration. If anything your blow test would seem to show it filters better but I don't think that's the case either
If you look at what/whom I quoted, you'll see that my comment was NOT directed towards yourself!! I'm glad to see at least one other person in this country has not totally given up on their own country's companies/products (and is not so glee/joyful at an American company's demise)!!quote:
Originally posted by OriginHacker21:
Hey dailydriver - didn't mean to come across as a GM hater. Actually, I'm a GM only buyer (I own a 2004 Pontiac Sunfire). I plan on taking it to 400,000 miles so...My next car will be GM as well. Haven't had any problems with my car either.
It would be nice to see GM go to 60k or so as that says "We believe in our product."
That is so lame.quote:
Originally posted by dailydriver:
I'm glad to see at least one other person in this country has not totally given up on their own country's companies/products (and is not so glee/joyful at an American company's demise)!!
You must be an Auto Union member hiding behind fake patriotism.
GM must be reformed, period!
UAW is the most unpatriotic egoistic bunch cariyng only about themselves and their outrageous benefits.
UAW has cornered GM into a corner. The management offered no resistance. Blame them, not the American public.
For every active employee, GM pays pension benefits and health care for 2.5 retirees.
And it will only get worse.
GM is fundamentally uncompetitive.
You can't hide this fact, no matter how much you wave the American flag.
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