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Author Topic:   Controversial Topic...Air Filters!
chomme
Member
posted January 13, 2004 10:28 AM
I run a 14x5 KN with a pre filter on a street stock.

The KN still looks like new after 2 seasons. The prefilter stops it all.

istock59
Member
posted January 13, 2004 11:43 AM
Wix 4"X14" paper. Run a prefilter for hotlaps and heat race, remove the prefilter for feature.

Change air filter when I change oil filter. Or if there's a REALLY dusty night, I'll change it afterward....

dirtbuster
Member
posted January 13, 2004 11:44 AM
just curious why they outlaw the K&N?


chomme
Member
posted January 13, 2004 11:53 AM
I run Wix & only Wix. A couple of years ago a buddy of mine had his engine in getting freshened at the same time I had mine in. I could not believe the dirt inside the intake and how much more worn his bearings looked. We both used Mobil 1 and I think mine even had a few more nights (as a side note my friends engine came from another builder who went out of business during the season). His philosophy is this: "I could let my customers use Fram oil filters, K&N air filters, dinosaur oil and probably do alittle more business by doing more rebuilds or I could tell them what I know and show them the difference---hopefully that's enough to them appreciative and coming back along with telling other racers."

Bill Hendren (respected builder in his own rite) is on this site often, I'm sure he'll agree with that statement.

dirtracer7
Member
posted January 13, 2004 12:33 PM
paper is the best filter but gets full quiker k&n flows more air but also flows more dirt.I been using an amsoil 2 stage foam filter which is supposed to flow better than paper and equal as far as collecting dirt.I been using this 2 years now and no dirt in the carb and intake cylinders look good.It is a higher maintenece than paper, I clean and reoil after every trip to the track.As with everything poor maintenece = poor longivety.


dirtrace
unregistered
posted January 13, 2004 01:02 PM           
I think rules often outlaw K & N filters because at larger open pavement late model races 7500-20,000 to win. I have seen guys run dry new k/n filters. Which would be like running none basically, but they sure would get some air..



NJantz
Member
posted January 13, 2004 01:14 PM
I agree with everyone who is for the paper filters. There are a number of drawbacks to the K&N filter, and most of these are listed above. Another aspect is the horsepower loss. Yes......I said horse power loss. For those that believe advertising, this will be difficult to comprehend. But the simple facts show in dyno testing, both engine and chassis dyno. In every single test that we have done, a Wix filter will produce more power than the K&N. Even a clean, fresh oiled K&N has more restriction than the Wix. This is seen through HP loss, as well as an air/fuel reading that goes rich when putting the K&N on. We have also tested both filters in a "raced" condition. The results are even more dramatic.

GO 24 is correct, and its good to see that he has a honest engine builder. I have literally seen engines bore themselves after 1 season on a K&N, and these were not engines owned by people too lazy to clean the filter.

Bottom line............ if you make an investment in a race engine, switch to a paper filter and protect your investment.

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


2nd2none
Member
posted January 14, 2004 06:13 AM
whats the part number for a 14" wix? Whats the tallest filter they make or can you double stack 2 filters then cover with outerwares.


True Blue
Moderator
posted January 14, 2004 06:19 AM
The reason the cotton gauze filters are outlawed by many sanctions that time trial is the Cotton filter is thought to be able to hold " performance enhancing" chemicals to improve lap times for a lap or two.



norightturn
Member
posted January 14, 2004 11:32 AM
There is a place in canada i think its name is ram air box. They make custom air cleaner boxes and they sell k&n .K&n tech line gave me there number, after talking to them they basically said k&n is junk and when you put a pre filter on them they found them more restrictive in their own testing .I also seen other people at the track complaining about dirt in their carb.go figure.


norightturn
Member
posted January 14, 2004 02:36 PM
K&n filters CAN be sprayed woth NO2 and they slowly blead it out for about 30-50 seconds. We have proven this in a test and lost almost 1 second on a 14 second 3/8 mile asphault track.
As for dirt in the intake - NO air filter should alow dirt into the engine, and if it did it would cause problems in the top of the cylinder and sever ring problems. The dirt is more than likely going through the carb to base flange area, or through the choke shaft holes if they are not pluged.
Run a air cleaner to filter base gasket or a small piece of vacume hose around the base.
We have run several 100-200 lap modified and late modle races on dirt and never found dirt in the intake. We built a street stock far someone who ran a season on dirt and ran a K&N and a pre filter and only hosed it off each week, and only changed his oil 3 times in the season and we never found anything in the intake.


Whitelightning
Member
posted January 14, 2004 07:43 PM
Been running wix for ever on my dirt track car never ever had a probem and I run the 2096 wix. Always have clean carb and never had a problem. Not sure why but all the late models here run a wix and if its good enough for there engine it must be good enough for my pure stock, lol. Not saying that just because someone else does something it makes it right but I know there engines cost more and they spend more money and time researching and there gonna run what is the better choice and what the know works. I do have a k & n in my truck but I dont race with 20 other cars kicking up dust,dirt, and mud everywhere in around me. Oh, I almost forgot what does nascar run, Not k & N lol


modracer09
Member
posted January 14, 2004 09:45 PM
Well im Canadain and i run k&n it works fine i allso run the k&n filter lid and boy you can hear it suck in the air when you lift off the gas. we clean them both every week and alsorun an outerswears pre filter but they work fine if maintand properly also i might try the green ones forget the name.

just my 2 cents

dirtracer7
Member
posted January 15, 2004 08:14 AM
that just goes to show you different strokes for different folks.Maintenece is the key to any filtering system keeping a clean filter = a clean motor. There ain't nothing being said about canadians here,that just happens to be were a buisnees was that I had talked to.they make custom air cleaner boxes!!!

[This message has been edited by dirtracer7 (edited January 15, 2004).]

sdhnc29
Member
posted January 15, 2004 09:55 PM
Man.......... what a complex topic! Good job chomme ! LOL Makes for some good reading.

You can leed a horse to water, but you can't make him drink.

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


outlawstock17
Member
posted January 16, 2004 05:24 AM
agreed.....good topic. okay steve, you led this horse to water.......but i'm no DONKEY......i think i'll take a sip and see if it tastes good. if it does, i'll drink the whole trough!

i've ran the k & n for years and never experienced any dirty carburetor or worn out bores. i've always used the k & n foam fre-filter too......but if a wix filter flows better and makes more power, i'm all over it. that would be the cheapest HP i've ever gained!

outlawstock17
Member
posted January 16, 2004 05:29 AM
one more thing, steve? will i need to re-jet? 3 sizes fatter?


Ego Racing
Member
posted January 16, 2004 05:58 AM
Whitelightning In Nascar K&N filters are not allowed by the rulse due to the ability of the filter to hold nitrous as I said above. A NEW paper filter will flow slightly more than a K&N but when paper gets dirty it starts to close, also NEVER get one comopletely wet as it will plug shut. That is why the cars that do run paper change them every race or at least every weekend. There must be a reason that the Military switched all of their engines over to K&N during Desert Storm. They were having problems with the Apatchie (?) Helecopter due to dirt entering the turbine. They switched to K&N and it corrected the problem.


ratracer10
Member
posted January 16, 2004 07:38 AM
I will try to find the pictures my brither sent me of them unloading K&N boxes off of a cargo transport and holding the helecopter filter. He was one of the maint men who were doing the change out. They may have changed by now or even during the war itself, but it was K&N filters they were using.


dirtracer7
Member
posted January 16, 2004 02:01 PM
What does the military know? There the ones who buy 1000.00 hammmers and 1500.00 toilet seats.I was a helicopter crew cheif /mechanic when I was in the army.The ones I worked on had a dirt separater not a filter .it seperated the dirt and blew it out the side clean with soap and water.The way you cleaned the inside of a chopper engine was to spray soap and water in it and crank it over.Turbines suck massive amounts of air in I can't imagine a k&n could handle that volume.them filters where to put in iraqs truck so they would take a dump just kidding LOL.they might have been there for the hum v or trucks.

[This message has been edited by dirtracer7 (edited January 16, 2004).]

UNVRNO
Member
posted January 16, 2004 10:05 PM
UNVRNO, why couldn't a paper filter make more power AND filter better? isn't that what k & n claims their filters do?

i'm not convinced either way, but i'll try the paper one and come to my own conclusion.

[This message has been edited by outlawstock17 (edited January 16, 2004).]

sdhnc29
Member
posted January 16, 2004 11:21 PM
UNVRNO ,

First of all I do not sell air filter's, I build what they are supposed to be filtering. I could basically care less what you or any other person that is not a customer of mine uses for an air filter. My duty to the customer's that I have is supply them with the most power that I can produce for the money they are spending with me. In doing so, I have (along with my father who has done the most R&D) done extensive product testing. This includes everything from oil , to carb spacers, intake manifolds, fuel, carbs, valve train component's, piston ring packs, rotating assemblies, cylinder heads, AIR FILTER's, and so on and so forth. So why in the **** would I fabricate a story on air filters, post it on this site, and deliberately mislead everyone into buying a paper element air filter that I don't even sell?????????? Those with common sense, and those that have read my past posting's on similar subject's would know that I don't post lies, fabrications, brain-fart ideas, or any other ****. What I post is based on my R&D work or past experience.

So UNVRNO, my best advise is rent 8 or 9 hour's of dyno time, test every conceivable scenario with the K&N vs. paper, Flow Control vs. Sure-Seal........... and post your educated opinion or findings. Having been born and raised in California, and knowing about The Carb Shop, I can understand your ignorance on this subject.

Bottom line is I come on here to help racers, and offer free advise. I get nothing from this help other than the great feeling of helping accelerate the learning curve for those who need help. Some will agree with me, and some will disagree with me, same as everything else in life. All I do is make factual post's on what I know to be FACT from my own testing and experience. If your relying on magazine tech articles, auto parts store gossip, etc. , then you are not getting accurate info on most subjects. Kind of like relying on the main stream media for unbiased reporting .........lol

If anyone would like to PM me or email me and ask for me to explain my stance on this topic, I'll be happy to do so in my spare time. My original post was a simple "non-technical" explanation. Other than that, I am finished replying to this topic.

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780
Check out my other business at www.solemnvow.com A special thanks to jammin for the awesome job he has done for me on this site!!


rocket36
Member
posted January 17, 2004 04:24 AM
i think that both paper & oil type would be good in certain aplications. but both are garbage if there full of dirt. formula one cars, which make more than 800hp from 3litres (engine size) at some 19000rpm (bmw/williams) is a pretty good testimate to the fact that most air filters are capable of far exceeding the flow capabilities that our engines require. they all run an air filter but what style i don't know.
just something to think about.

[This message has been edited by True Blue (edited January 17, 2004).]

UNVRNO
Member
posted January 17, 2004 09:32 AM
K&N's claim is their filters flow more air dirty than others. How long can an air filter stay clean as in (NEW CLEAN) on a dirt racecar?


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