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YOUR RESEARCHHow many mile are K&N airfilters good for??
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would result in something
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Suspected cause
If my 01 C4 were to somehow suck in 60% more airflow I would fully expect the engine ecu to use the proper mixture ratio which I suspect would result in something on the order of 465HP, until the engine self destructed a few seconds later anyway.
Leading evidence: 'would result in something' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'would result in something' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Clean don't over oil and let it sit' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion
When cleaning don't over oil and let it sit on newspaper over night.
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Suggestion
Unlimited (ten years) - they should be cleaned every 30k-50k miles.
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Suggestion
This will decrease the chance of setting off your mass air flow sensor.
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Suggestion
These tests are performed in accordance with the Society of Automotive Engineer's testing procedure.
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Suggestion
Nobody asked me but had I been asked I would have said use the minimum amount of air filtration that gives us the best performance but still with 99.99% probability that the engine will last 24 hours.
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Suggestion
If my 01 C4 were to somehow suck in 60% more airflow I would fully expect the engine ecu to use the proper mixture ratio which I suspect would result in something on the order of 465HP, until the engine self destructed a few seconds later anyway.
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would result in something
No successful repair reported for this finding.
0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that suspect a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suspected cause
If my 01 C4 were to somehow suck in 60% more airflow I would fully expect the engine ecu to use the proper mixture ratio which I suspect would result in something on the order of 465HP, until the engine self destructed a few seconds later anyway.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
17 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261027T201111Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Unlimited (ten years) - they should be cleaned every 30k-50k miles. When cleaning don't over oil and let it sit on newspaper over night. This will decrease the chance of setting off your mass air flow sensor.
Rob
Are you at work or at home now?? My 996 is in CA and I'm in TX. I am packing and need to know the width and length of the trunk. If you have access to your car could you measure the dimensions. I have to leave in around 1.5 hrs so if you can measure before then great, if not thanks anyways.
K&N
Only good for as long as it takes the owner to figure out: A}It was a waste of money (NO GAIN!) or: B} the oil that wicks off the filter and into the intake airstream musses up the mass airflow sensor.
Musses up....contaminates the mass airflow sensor enough to foul up the fuel/air mixture and thereby over the long term result in fatal engine failure. When that happens be sure and remove the K&N before asking the dealer about warranty repairs.
It is against the law (Magnuson-Moss Warranty) for a manufacturer to require the use of a specific brand of air filter unless it provides a free replacement air filter.
They come pre-oiled just don't over oil when cleaning, to be safe buy a new one.
Porsche uses BMC (virtually the same as K & N) in their race cars.
K &N claims it increases air flow by 60%
IMHO it also improves the sound.
Increases air flow by 60%...
WOW!! 465HP amazing!
I think you really mean decreases airflow resistance by 60%...
And there's only two ways to do that:
More filter surface area...more "pores".
Less filtration capability...larger "pores".
Yeah these K&N filters are really not worth it. Ask yourself why they never publish any dyno results in their ads. Not a one. But we do get to see a little ping pong ball go up higher in a tube... Gimme real before/after dyno readings, or gimme a break.
Air flow does not directly correlate w/HP, though less restriction does provide more efficient combustion.
Air filters are not rated by micron size on an absolute basis. The proper rating system for air filters is a testing procedure developed to measure the efficiency of the filtration media at varying micron sizes. These tests are performed in accordance with the Society of Automotive Engineer's testing procedure. K&N air filters have an overall efficiency rating of between 97% and 99%, exceeding industry standards.
As far as dyno results, the density of air varies with both the weather and altitude. There is more air in the same amount of space when the weather is cool than when it's hot. One way to get a performance boost is to only drive in cold weather. Since air is variable, air flow claims in absolute terms are not meaningful.
465HP was a PUN....
But not altogether...
If my 01 C4 were to somehow suck in 60% more airflow I would fully expect the engine ecu to use the proper mixture ratio which I suspect would result in something on the order of 465HP, until the engine self destructed a few seconds later anyway.
I wonder...
Does filter efficiency really come into play at any time except at, or near, WOT?
And at WOT, HIGH flow rates, does the lack of higher atmospheric pressure become a greater limiting factor than the few percentage points of additional efficiency that might be gained from a freer flowing, K&N, filter?
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by wwest:
<strong>465HP was a PUN....
</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">LOL- you obviously don't know what a pun is.
I'm not sure about your second point either. In a NA engine at WOT the air density approaches that of atmospheric pressure. When the air density is less than atmospheric pressure a vacum is measured in the intake manifold, i.e. during idle.
I guess there is no good reason to have one <img border="0" title="" alt="[Wink]" src="wink.gif" /> <img border="0" title="" alt="[Wink]" src="wink.gif" /> <img border="0" title="" alt="[Wink]" src="wink.gif" />
...unless of course you are winning the 24 hours of Daytona or LeMans or ???
<img src="http://pw1.netcom.com/~ljcook/images/GT3RS_BMC.jpg" alt=" - " />
24 hours of Daytona.
Car #5, a Lola/Nissan came in first in class and seventh overall. You might have noticed that the rear spoiler said something like "West Family Foundation".
Nobody asked me but had I been asked I would have said use the minimum amount of air filtration that gives us the best performance but still with 99.99% probability that the engine will last 24 hours. A chicken wire filter may have met that criteria.
And, I'd have to check but I don't think K&N was one of our sponsors. Had they been, then I have no doubt that we would have been using a K&N regardless of actual benefit, other than having their money.
We get to present $150,000, lap pledges, to Seattle Children's Hospital next week.
Even though 60% more airflow at the same pressure drop across the filter (vaccuum in a car application) isn't important the correlary to that, the pressure drop across the filter at the same flow is. It means a filter with less restriction causes less vaccuum and makes your engine lose less power sucking air past the filter. That is more efficiency and less Pumping losses. That applies across the operating range not just WOT. As pointed out how you get there is important. If it's larger pores, the engine also getting more dirt. I have never seen any results of K&N versus paper filters for particle filtering at their expected flow rate. That would be interesting.
Tell me why "restricted" (say OEM paper vs NONE) flow rate is important at any point below, or very near, WOT?
I have the throttle 50% open but only get 45% flow rate. If I can even sense the difference all I have to do to correct the matter is add a little "lead" to my foot.
And, hey, if 60% less resistance to flow resulted in 60% more flow then my 99 C2 would have 450HP.
Efficiency of OEM filter 91% (guess)
K&N 60% improvement = 96.53% efficiency
factory HP 300+/-10% 270-330HP
K&N HP 315+/-10% 268.5-331.5HP
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