dondi0210

I dont know if someone already posted about this but I'm glad i found the right K&N for my '13 OS SE.....

rotterdam

How do you find the gas mileage?

Do you notice any difference with performance / sound / fuel etc?

Please let us know.

powellwm10

I second that^
I want to get one but I've looked at my local Advance/Auto Zone but to no avail. Guess I'll have to order from knfilters.com. Im just dragging my feet on it though.

AWCAWD

I hate to be the one, who always spoils the fun but I would caution people to blindly install high performance filters. One should wonder first, if the K&N and Cosworth filters are so great why the manufacturers are not installing them in masses in new cars. According to the claims they would provide higher performance and reduced fuel consumption so, it would be a win-win situation for everyone. The added cost would only be ~$25 or so. I think the answer lies in the history of these high flow filters. They were introduced to racing, where performance matters only and longevity is not a factor at all (car manufacturers on the other hand must provide warranties; in case of Mitsubishi it is a generous 10 years). One has to consider the associated risk in reducing engine lifetime before installing them. There is no free lunch: higher flow can be achieved by trading the filtering ability (the laws of physics cannot be violated). There are diehard defenders of these filters but the danger of uncontrolled internet publishing (lack of peer review) is that the perceived truth is in the eye of the beholder unless credible sources are used to support the claims.
There are three questions to be addressed:
1. What are the sizes of abrasive particles that may be sucked in the engine?
Sand grains generally vary from 2 mm to 60 um (micro meter; there are no Greek characters here) but long-term suspensions can contain particles smaller than 20 um
http://www.wmo.int/pages/prog/arep/wwrp/new/source.html
Dust particles collected from multiple sites in Colorado showed a typical size of ~30 um but as small as 1 um particles were found (in 10 % of the total dust). Please see Figure 8 in the following link:
http://esp.cr.usgs.gov/projects/sw/s...LM_report.html
Mineral dust aerosols have a typical size of 10 um:
http://arxiv.org/ftp/arxiv/papers/1110/1110.1562.pdf
Let us not forget salt particles (as abrasive and as corrosive agents either introduced naturally near oceans or by salting roads in winter). Sea salt aerosols can have characteristic sizes <25 um to 50 um:
https://books.google.ca/books?id=AEI...20size&f=false
http://www.ipcc.ch/ipccreports/tar/wg1/169.htm
2. What is the minimum particle size that may damage the engine?
According to a SAE study wear caused by abrasive particles in engine oil can be reduced by as much as 70 % if filter size was reduced from 40 um to 15 um:
http://papers.sae.org/881825/
Given that the main source of damage is caused by friction it is reasonable to assume that the same 15 um size can be considered as the lower threshold for piston/cylinder system.
3. What are the pore sizes of the air filters? This information is not readily available as manufacturers do not state this in their specs.
Paper filter: ~30 um
http://www.gasgoo.com/showroom/19870...s/1110349.html
K &N filter: The only explicit data I could find is for a K & N drycharger filter pore size (127 um) that protects the actual air filter.
http://www.knfilters.ca/news/news.aspx?id=1235
This should mean that the pore size of the air filter must be smaller than 127 um since this item is for protection.
The following standardized (ISO 5011) test was done to evaluate how much dirt is captured by various filters:
http://www.nicoclub.com/archives/kn-vs-oem-filter.html
According to this test paper filters allowed only 0.1-1% of the dirt to pass through, while K&N filter let 3.2 % of dirt unfiltered. That should mean that the pore size of a K&N filter is definitely higher than 30 um but less than 127 um. One can do the following test: try to push through the filter a human hair (~70 um diameter). If it passes through then you are out of luck because it will allow not only the hair but much of dirt as well. K&N in its “Million Mile Limited Warranty” uses the Magnuson-Moss Warranty Act to cover its back but never states that K&N filters are just as efficient as paper filters.
http://www.knfilters.ca/filtercharger.aspx

I think it is obvious that K&N filter can shorten the lifetime of the engine. If someone intends to use the car for only few years then it might be OK for the original owner depending on the location and use (eventually someone has to pay the price for the damage caused; may be the next owner).

Redstang69

I must say that I don't have all the facts to back up what AWC says, but I definitely can agree that one should do this with caution. When I was heavily into 4wheeler racing and doing a little engine building there a significant amount of people that I read about that would have engine failures that could be attributed to a K&N filter. The data the AWC provided is the most unbiased and factual that I've seen yet, and common sense would somewhat prove that in order to get more air flow, one must sacrifice something in order to get that.
This topic is as highly debatable as what engine oil to run. What people really need to look at is a better way to get air into the box. I intend to cut a spot out of the plastic piece in the front so that it's a much more direct airflow into the snorkel/box.

mRVRsport

There's no doubt the possibility of ingesting a bit more dirt can occur when using a K&N (or any other similar filter).

Few things to keep in mind -
- K&N filters do require the proper application of the oil to the filter element to work.
So, if too little is applied, then more dust&debris will get through. Along with the other end, if too much is applied the risk fouling your MAF senser.

- If you're already driving in a dusty environment. Then perhaps it's wise to not use these types of filters, to begin with.

- Lastly, our vehicle's intake system is VERY unique! If you look at it carefully, our airbox path > Actually forces the air to take a 180 degrees turn from the direction of the airflow to get to our engine. Any dirt/debris would have to make it thru the filter AND then make a fairly sharp turn within the airbox before it can have a chance to get to our motor...

>> So, perhaps our vehicles CAN still take advantage of K&N filters even with all the facts ("possible" negative effects) presented to its usage.

dondi0210

I noticed more pick up, sound almost the same, I can just hear it sucking air. Haven't check my gas mileage yet though.

mRVRsport

Here's an interesting thread >
(It's not directly related to our particular K&N filter, but the results of this person's experience should be noted.)

LINK

infected

If the oil is such a concern yet you still want some performance gains, might as well pick up a CAI with a dry filter. The AFE filter on my Takeda is super easy to clean. Rinse with water and air dry. No hassle. Otherwise maybe you're better off staying stock?

Thanks for sharing the PN, OP.

AWCAWD

Below one can find a link to a test (from a reliable source) performed as a real world acceleration test of a same car with K&N performance filter and stock paper filter. The results were identical. (if you want to save time go to 7:03 directly for the result). One can draw the conclusion whether it is worth to replace the stock filter or not.

Landshark

a long time ago back on the old Porschelist forums, a guy tested a K&N filter vs. a stock 928 paper air filter on a flowbench ... results: the paper filter passed more air.

depending on the application, they possibly may *INITIALLY* pass more air (assuming the balance of just enough filter oil), but its been shown they quickly pass a lot less than paper once a bit of dirt starts to accumulate. the sucking intake sounds do not equal more performance.

i run a dry drop-in filter on my car - i don't know if it increases performance, but i bought it because:
1.) it is easy to clean with a couple blasts of compressed air vs. cleaning/drying/oiling
2.) it is reusuable and i don't have to run around looking for replacements

if you can find a dry drop-in panel filter for the OS, i'd do that, but not sure they make them for it or not ...

coldsteel82

AWCAWD

A comprehensive test of air filters (air flow and filtering ability):