So 2 drop in K&N air filters, will do nothing....

shesha · 05-22-2009, 11:48 AM

for HP??? It's a waste of money right?

nogoodname · 05-22-2009, 11:50 AM

not really, it lets the engine breathe better. like a stuffed nose compared to a clean nose......but then we hear stories of the air filters being too flowing and letting in dirt.

shesha · 05-22-2009, 11:59 AM

Really? Thats intresting, I guess I will leave it as is then.

wstar · 05-22-2009, 12:15 PM

I think a couple of people have already dyno'd dropping K&N filters into the stock airboxes on a stock car, as well as removing the air filters completely on a stock car, and seen no noticeable gains. The stock intake design is the limiting factor, not the filter.

frost · 05-22-2009, 12:23 PM

I dont see how air filters soaked in oil have better "breathability" than a dry cotton filter.

wstar · 05-22-2009, 12:35 PM

Quote:

Originally Posted by frost

I dont see how air filters soaked in oil have better "breathability" than a dry cotton filter.

The basic argument for K&N's approach is that the filter media they're using has huge holes in it. If you ran a K&N filter dry, it would get way better flow than anything else, at the cost of letting tons of dirt through. Their design idea is to use a way-too-breathable-for-safety filter media and then wet it with oil so that the dirt sticks to the oil instead of going into your engine. They really do flow pretty well, better than stock anyways. I can't comment on how they compare to other non-stock options like the Cosworth though.

And yes, there has been some long-running debate between K&N and their detractors about whether the K&N setup is bad for your engine, either because even with the oil it still lets too much dirt through, or whether the oil itself flows into your intake in very small concentrations, which builds up on your MAF/MAS sensors and causes them to degrade and read incorrectly.

K&N's side of the argument is that they do extensive SAE-backed testing of their product, and it filters to industry specs and does not introduce their oil onto your MAF, assuming you oil it properly (and blaming over-oiling for the MAF issues essentially). The detractors have had labs do tests that seem to contradict in some areas though. I honestly think most of the debate comes down to whether the K&N filter in question is perfectly maintained and has exactly the right amount of oil (too little = dirt gets through, too much = K&N oil on your MAF sensor).

In any case, lots of people use them and for the vast majority of people they seem to work fine.

frost · 05-22-2009, 12:44 PM

But there is no real guideline for how much oil people put on those things. People practically dunk those things in oil, then go for a drive. Airflow gains seem only possible by using very little oil, which would of course let too much dirt in. I mean, I'm far from an engineer, the concept just seems debatable.

Josh@STILLEN · 05-22-2009, 12:51 PM

Quote:

Originally Posted by wstar

The basic argument for K&N's approach is that the filter media they're using has huge holes in it. If you ran a K&N filter dry, it would get way better flow than anything else, at the cost of letting tons of dirt through. Their design idea is to use a way-too-breathable-for-safety filter media and then wet it with oil so that the dirt sticks to the oil instead of going into your engine. They really do flow pretty well, better than stock anyways. I can't comment on how they compare to other non-stock options like the Cosworth though.

And yes, there has been some long-running debate between K&N and their detractors about whether the K&N setup is bad for your engine, either because even with the oil it still lets too much dirt through, or whether the oil itself flows into your intake in very small concentrations, which builds up on your MAF/MAS sensors and causes them to degrade and read incorrectly.

K&N's side of the argument is that they do extensive SAE-backed testing of their product, and it filters to industry specs and does not introduce their oil onto your MAF, assuming you oil it properly (and blaming over-oiling for the MAF issues essentially). The detractors have had labs do tests that seem to contradict in some areas though. I honestly think most of the debate comes down to whether the K&N filter in question is perfectly maintained and has exactly the right amount of oil (too little = dirt gets through, too much = K&N oil on your MAF sensor).

In any case, lots of people use them and for the vast majority of people they seem to work fine.

K&N actually has created a testing facility and done ridiculous testing to fight the internet rumor that MAF sensors can be damaged by their oil, and are even willing to get involved at the dealership level for any dealers attempting to claim/charge customers for any issues and blaming an oiled filter as the cause.

We've been using K&N filters on all of our intakes since forever and have had no problems.

RCZ · 05-22-2009, 01:47 PM

Umm....I ran the stock intakes without filters on my stock car and it made 0 more horsepower than with the filters in place...

wstar · 05-22-2009, 01:55 PM

Quote:

Originally Posted by Josh@STILLEN

K&N actually has created a testing facility and done ridiculous testing to fight the internet rumor that MAF sensors can be damaged by their oil, and are even willing to get involved at the dealership level for any dealers attempting to claim/charge customers for any issues and blaming an oiled filter as the cause.

We've been using K&N filters on all of our intakes since forever and have had no problems.

And I've got K&N filters from Stillen on my car right now, so that should tell you about what I think about this whole issue. Just trying to give a quick and fair rundown of the debate

Josh@STILLEN · 05-22-2009, 02:12 PM

Oh I wasn't disagreeing with you.. I was just adding a point to what you said, and adding the info on their support..

As you can imagine, that's been a hot-button for them.. you know how those internet rumors can explode.. "my buddy totally had problems with XXXX"

05-22-2009, 02:15 PM

Quote:

Originally Posted by Josh@STILLEN

We've been using K&N filters on all of our intakes since forever and have had no problems.

My brother ordered a Stillen intake for his 240sx and never had a problem.

NIZMOZ · 05-22-2009, 02:39 PM

Quote:

Originally Posted by RCZ

Umm....I ran the stock intakes without filters on my stock car and it made 0 more horsepower than with the filters in place...

Well mine made a few hp vs stock on the dyno and especially after a tune.

semtex · 05-22-2009, 02:48 PM

Quote:

Originally Posted by NIZMOZ

Well mine made a few hp vs stock on the dyno and especially after a tune.

What did? K&N drop-in filters?

wstar · 05-22-2009, 03:32 PM

Quote:

Originally Posted by NIZMOZ

Well mine made a few hp vs stock on the dyno and especially after a tune.

Were those track filters or street filters though?

05-22-2009, 11:48 AM	#1 (permalink)
shesha Base Member Join Date: May 2009 Location: Los Angeles Posts: 159 Drives: 370z Silver Rep Power: 15	So 2 drop in K&N air filters, will do nothing.... for HP??? It's a waste of money right?

05-22-2009, 12:15 PM	#4 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	I think a couple of people have already dyno'd dropping K&N filters into the stock airboxes on a stock car, as well as removing the air filters completely on a stock car, and seen no noticeable gains. The stock intake design is the limiting factor, not the filter. __________________ 7AT Track Car! Journal thread / Car setup details

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05-22-2009, 11:50 AM	#2 (permalink)
nogoodname Lifetime Premium Join Date: Nov 2008 Location: Montreal Posts: 22,357 Drives: E46 M3 Rep Power: 1764	not really, it lets the engine breathe better. like a stuffed nose compared to a clean nose......but then we hear stories of the air filters being too flowing and letting in dirt.

05-22-2009, 11:59 AM	#3 (permalink)
shesha Base Member Join Date: May 2009 Location: Los Angeles Posts: 159 Drives: 370z Silver Rep Power: 15	Really? Thats intresting, I guess I will leave it as is then.

05-22-2009, 12:23 PM	#5 (permalink)
frost Retired admin Join Date: Dec 2008 Location: Winterfell Posts: 106,613 Drives: Your Wife Crazy Rep Power: 0	I dont see how air filters soaked in oil have better "breathability" than a dry cotton filter.

05-22-2009, 12:44 PM	#7 (permalink)
frost Retired admin Join Date: Dec 2008 Location: Winterfell Posts: 106,613 Drives: Your Wife Crazy Rep Power: 0	But there is no real guideline for how much oil people put on those things. People practically dunk those things in oil, then go for a drive. Airflow gains seem only possible by using very little oil, which would of course let too much dirt in. I mean, I'm far from an engineer, the concept just seems debatable.

05-22-2009, 01:47 PM	#9 (permalink)
RCZ A True Z Fanatic Join Date: Nov 2008 Location: Miami Posts: 6,403 Drives: '09 370Z Rep Power: 1118	Umm....I ran the stock intakes without filters on my stock car and it made 0 more horsepower than with the filters in place...

05-22-2009, 02:12 PM	#11 (permalink)
Josh@STILLEN The370Z.com Sponsor Join Date: Dec 2008 Location: Costa Mesa, CA Posts: 1,197 Drives: 2004 G35 Coupe 6MT Rep Power: 533	Oh I wasn't disagreeing with you.. I was just adding a point to what you said, and adding the info on their support.. As you can imagine, that's been a hot-button for them.. you know how those internet rumors can explode.. "my buddy totally had problems with XXXX"