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-   -   K & N air filter (https://www.subaru-svx.net/forum/showthread.php?t=52842)

ensteele 02-03-2010 10:09 PM

Re: K & N air filter
 
Quote:

Originally Posted by Trevor (Post 633378)
This is a lot more than a good and should go into the how too stuff, or become a sticky. Please can someone make this happen.

I will make it happen Trevor. We are about to do the upgrade in software and a new how-to section. :) I will sticky it for the time.

shelfy 02-04-2010 09:33 AM

Re: K & N air filter
 
interesting...could this be the cause of the chugging, as i call it?

Trevor 02-04-2010 01:33 PM

Re: K & N air filter
 
Quote:

Originally Posted by ensteele (Post 633405)
I will make it happen Trevor. We are about to do the upgrade in software and a new how-to section. :) I will sticky it for the time.

Thank you Earl,

The "how to" section is certainly due for an edit and sort out, as it forms such a very valuable part of this forum.

Trevor.

immortal_suby 02-04-2010 03:42 PM

Re: K & N air filter
 
Quote:

Originally Posted by LetItSnow (Post 633399)
Take any given number of grams of dirt, remove the amount that the oil filter would remove, and divide it by the number of oil changes that your properly maintained car would have before its air filter was restricted to over double its resistance as new? Not much.

I think the point is that the dirt makes it into your intake, past the valves, down to the pistons, past the rings and cylinder wall, and then chugs around in your pan while mixing in with the oil where it is again passed up to your crank bearings, etc until it would finally make it to your oil filter to be removed.

All the while possibly damaging anything in it's path.
The question is - are the size of the particles passed large enough to do damage with the clearances in our engines?


To me it's irrelevant. I simply don't want to put that much extra dirt into my engine when I plan on keeping my cars for hundreds of thousands of miles.

A while ago I calculated the cfm at peak torque for our 08 tribeca to determine if the stock paper filter was starving it. It was not. It flowed more than enough. With 0.3 L less displacement and the larger filter that the svx has, I feel confident that a paper filter in our airbox also flows more than enough air. This makes the performance claim of K&N simply not true in a stock svx.


So - more dirt and no more performance. What is the point of the K&N? Oh yeah, it lasts a million miles. :WTF:

LetItSnow 02-04-2010 05:32 PM

Re: K & N air filter
 
Quote:

Originally Posted by immortal_suby (Post 633481)
...that much extra dirt...

Legitimate question: How much extra dirt?

How long would you say it takes for your airbox to see a pound of dirt? Miles or time - your choice.

How big (volume) is a pound of dirt? How about 6.6 grams (the difference between the thread-subject-chosen K&N and the best-in-test AC Delco)?

Would you eat 6.6 grams of dirt for a dollar? How about over the course of a year?

Don't let percentages and bench tests that don't reflect real world situations scare you; look at real, raw numbers before declaring that the end is nigh.

immortal_suby 02-04-2010 07:58 PM

Re: K & N air filter
 
I had a k&n on my little red wagon for a long time. The oil was black before I even hit 3k mile change interval every time. I always hated that but didn't know the filter was the cause. I put that same piece of junk filter into my svx when I first got it with the same results. Only later did I realize the filter was at fault and I threw that pos into the trash. With a paper filter my oil is still clean on the dipstick when I change it. I like that.

The test shows real numbers proving that the oiled filters let more dirt in. Whether they represent a minute, hour, week, month, or year of driving in the real world to achieve the specific weight is not estimated and would be difficult to test or guesstimate.

You can subscribe to the k&n advertisement pitch of more horsepower with no downside or you can choose to protect your engine as best as you can with a filter that is scientifically shown to filter more efficiently.

LetItSnow 02-05-2010 10:33 AM

Re: K & N air filter
 
The only thing I'm subscribing to is the fact that you can make numbers out to be whatever you want them to be.

It took damn near a quarter pound of dirt to end the test for the K&N (our topic subject, remember, and a filter bashed by SPICER pre-test, fwiw) and 0.22 cubic inch of the stuff got through the filter. That's smaller than a sugar cube!

I don't think that the sum of the dirt that found its way to the airbox in my Legacy and that in my SVX (combined, over 80k miles) has met a quarter pound. That would work its way out to a gram a year if SPICER's test's figures hold true.

In a four-oil-change year, that's a quarter gram. That's probably the size of a sesame seed. That's smaller than this emoticon: :tard:

I'm not going to tell you which filter is best for you, or which one is worst, and I'm not defending the K&N because it's in my car. I'm telling you that the numbers in the test are hype at best.

Numbers are numbers. What they mean is up to their appropriate interpretation.

I suppose you could decide that whether you eat a regular hamburger or a Big 'n' Tasty before you hit the dragstrip might critically influence your ET. After all, the Big 'n' Tasty is bigger, right? ;)

superdave555 05-01-2010 10:38 PM

Re: K & N air filter
 
What about oilless high flow air filters? How do those perform in comparison? ie a Green 2019? Does anybody run one of these and how does it perform?

Beav 09-23-2010 03:47 PM

Re: K & N air filter
 
If there was cheap horsepower to be had without compromising reliability don't you think the manufacturer would be all over it?

Instead of K&N why not fabricate some expanded metal screening, rice cakes and Wesson Oil for your filter? I can see this idea going viral in about 45 seconds... :rolleyes:

Roger Stephens 06-16-2011 02:33 PM

Re: K & N air filter
 
My '96 59k miler is on it's 3rd MAF with a standard air filter. It has a flat spot (half power) between 1,800 rpm and 2,400 rpm. After that, it's amazing - pulls like a train. Oh, and it's fine when cold. It's on it's second brand new MAF from Subaru but they last 1/2 a day and show up code 23 and the car runs like a moped. Any ideas anyone? There are only about 35 RHD left in the Uk so no-one has a clue here.....

dromano 04-24-2012 11:04 AM

Re: K & N air filter
 
Quote:

Originally Posted by immortal_suby (Post 631825)
And they let alot more dirt into your engine than a normal filter would.

This page is a good read if you are considering going to a K&N
http://www.duramax-diesel.com/spicer/index.htm

I'm convinced the dirt deal is settled science, I abandoned my K&N for stock. Way more dirt particles pass through the K&N than most any other AF.:eek:

david_12121 05-04-2012 12:06 AM

Re: K & N air filter
 
based on this video, which seems to be based on real data, air filters don't add power
http://www.youtube.com/watch?v=PAIxeQUSg-Q
now for the engine protection purposes, I doubt that a high flow air filter would do any better than the cheaper ones...but I haven't done tests on either...

bishop 10-23-2012 01:39 AM

Re: K & N air filter
 
An alternative would be the spectre filter.

http://www.autozone.com/autozone/par...3939_378103_0_

Conn SVX 10-23-2012 06:32 AM

Re: K & N air filter
 
BACK IN THE OLD DAYS I had a 1966 Dodge Dart GT 273 4 barrel . Someone stole my air cleaner. I replaced it with a small paper air leaner. Sounded great when that 4 barrel opened. Well after 35,000 miles the car was using a qt of oil in 500 miles. We took the motor apart and found that the motor was actually bored out by all the dirt that the crappy air filter let in . The ring gap was .050 over size . So between the ring wear and bore wear the rings lost there spring, and allowed the oil to pass. Moral of this story clean air is better than that 1/2 HP gain. <LOL> :rolleyes:

Cotton 07-11-2014 12:17 AM

Re: K & N air filter
 
I put one of these in about a year ago. I doubt it caused the problems I am having now, but this is an interesting thread. I will go back to a stock filter.


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