K&N air filter?

[Guest andywatson]

What's the part number of a K&N air filter for a 98 Legacy Outback? Has anyone ever had trouble installing a K&N filter?

 

My local Autozone ordered me one and their computer said I needed a 33-2232 model. I just checked the K&N website lists it as 33-2232 also. But I tried for a half hour last night to get that thing in there, and it appears to be about 1/8" too big.

 

Has anyone else had any success getting a K&N filter in the box? Do I have to totally remove the filter box from the engine compartment to get the lid back on it like the instructions say?

 

 

Thanks,

Andy

[Guest Legacy777]

too big how....too long, too wide, or too thick?

[Guest andywatson]

The BODY of the filter is the same as the OEM Subaru that I'm replacing. But it's the RUBBER LIP around the filter that is slightly bigger than the OEM lip. It's about 1/8" too wide and 1/8" too long, and maybe 1/16" too thick, which is keeping the lid from seating properly on the filter box.

[Guest Commuter]

I have a 97 OB. I think the air boxes are identical.

 

My K&N filter is a 33-2075. I have seen both numbers for our vehicles. They must be very very close in dimension.

 

I too had a fit of a fitment issue with mine. There is a slightly proud "lip" around the shoulder of the filter. The lip should go inside the box, while the shoulder sits on top. (And then the lid clamps down on it.) One could push it down into the box, but it would keep "popping" up. After fighting with it the first couple of times I cleaned it, I finally just took a utility knife and cut back the lip by about 2 mm. That is, I took off about a 2 x 2mm strip. This was off one end only. The filter was just a hint too long.

 

Problem solved. No more fighting with the darn thing.

 

Perhaps the same will work for you.

 

Commuter

[Guest andywatson]

Commuter, that's exactly my problem. The K&N book at Autozone listed the 33-2075 as the part I needed, but their computer listed a 33-2232, so when I had trouble getting it to fit, I thought maybe they ordered me the wrong one.

 

I contemplated hacking at it with a knife last night, but it was dark and I was pretty frustrated after fighting with it for a half hour, so I figured I should cool off and make sure I ordered the right part before cutting into it.

 

Sounds like paring down that lip should do the trick.

 

Thanks.

[Guest CROSSTBOLT]

The question is does the K&N really work or is it like the Tornado Air Management inlet turbulence generator: More money for something that does NOT work as advertised.

 

Karl

[Guest 99OBSter]

Sure it works, if by works you mean you don't want to ever replace your air filter again, ever.

[Guest Commuter]

Crosstbolt,

 

I noticed just a "hint" of difference in my car. Just a little more zip when accelerating. If you did a double blind test with me on it, I probably would fail. I doubt that I could consistently tell which filter is in.

 

I put one in my wifes Honda Odyssey as well. I should have looked at the filter first. The OEM one has pleats about 2" deep! I don't think I have any more surface area with the K&N... maybe even less. I didn't notice any difference, but then I don't drive the vehicle very much.

 

I consider it to have been worthwhile in my Subaru. And hold onto the old filter. Good to stick back in for a couple of days while you clean and fully dry and treat the K&N filter.

 

Commuter

[Guest 1 Lucky Texan]

Anyone know the REAL K&N part # for an '03 OBW 3.0 ? Ya'll have me convinced.

Carl

1 Lucky Texan

[Guest spagemurray]

If you want high SI levels then yeah get a K & N. Check http://WWW.BOBISTHEOILGUY.COM forum UOA section and you'll see why most UOA's on oil from K & N filter equipeed engines have very high SI which equls more wear, and most change back to OEM style real quick. If you want engine longevity forget it!

[Guest Legacy777]

SI levels??

 

care to elaborate on what that is?

[Guest spagemurray]

Silicon eg sand /dirt. I was going the K& N route till I read a bunch of UOA's and realised it's a no no. Racing yes, Street or even worse off -road forget it.

[Guest Chip Hedrick]

The part number for the K&N filter in my OBW is 33-2232.

 

I installed the K&N on 06/22/02 when my OBW had 74,600 mi. At the time, the OBW exhibited substantial low speed hesitation. I installed new OEM spark plug wires at the same time as the K&N, and the OBW's performance improved significantly. I changed two variables at once, so I can't say how much of the improvement was attributable to the K&N and how much to the new wires, but I suspect both played a substantial role.

 

The OBW now has 93,400 mi. Originally, the K&N was a very tight fit in the air filter housing, but it seems to have assumed the the shape of the filter housing and now goes in far easier. The K&N definitely is a worthwhile purchase.

[Guest spagemurray]

Chip do you before and after K & N UOA's to share with us?

[Guest Legacy777]

do you have a thing with acronyms? what the hell is UOA's?

[Guest 1 Lucky Texan]

I assumed it was 'used oil analysis' but I might be wrong.

 

Also, was the testing done under lab controlled cinditions or a 'self selected' survey? Was any testing done on what was stuck in the used filters? (oil AND air).

 

Face it, if they just asked for old oil from some rally racers and compared it to some 'soccer mom's' oil thats hardly conclusive.

 

Are details at that Bobsoil.... site?

haven't had time to visit.

 

Carl

1 Lucky Texan

[Guest Legacy777]

There's a thread on nasioc about where someone did testing between paper, k&n, & amsoil air filters, and the results were actually a little surprising.

 

I'll see if I can find it.

[Guest 1 Lucky Texan]

WOW does amsoil still sell filters?

I once owned a '69 datsun 2000 (srl311 - fairlady) and got tired of buying those weird factory filters. A guy that worked with me was an Amsoil 'pusher' and we found a round filter I could stretch and mash into the correct shape. So, later on I had my first kid - so of course dad's fun ride has to be repalced with a more 'sensible' car ('78 Civic sedan - with the trunk! cheapest car sold in America that year-eventually sucked a valve in cyl. #2 but that's a different story). So this 'nam vet at work bought the ragtop from me. Well, it BURNED TO THE GROUND 2 weeks later! He says it had a bomb planted in it because some bikers didn't like the girlfriend he was runnin' with! I SAY the pre-ignition it often had backfired through one of the Hitachi side-draft carbs. and ignited the Amsoil filter! We'll never know for sure. Anybody else hear of increased incidence of engine fires with oil soaked air filters?

Carl

1 Lucky Texan

[Guest spagemurray]

UOA is used oil analysis. Geez where you been hiding!. Look in air/oil filter section on BITOG and there are many UOA's with K & N air filters. Al have high SI levels which ain't good my friends. My Outback owes me too much money to touch a K & N thanks.

[Guest Legacy777]

Take a read over these.

 

www.bolhuijo.com/airflowtest/

www.mcagraphix.com/filter/test.htm

[Guest subyluvr2212]

Wow thanks Josh for those articles.

 

I agree that K&N filters are good in that they will last a very long time, since they only need to be cleaned and re-oiled once in a blue moon. But when I had mine, I noticed little more than better throttle response. I was wise to not expect 20hp gains like their ridiculous marketing scheme suggests, though...

 

But the fact that it's not the best <em>filter</em> worries me. Its only job is to keep stuff from getting in your engine. If you want maximum flow without caring about filtration, run with no air filter <img src=http://www.ezboard.com/intl/aenglish/images/emoticons/ohwell.gif ALT=":\"> ...

 

Oh, I use the el cheapo filters you buy at Autozone for $6 and have no power or torque complaints whatsoever

[Guest 1 Lucky Texan]

These are a good start. Better than the anecdotal stuff at the Bobistheoil..... site. As I thought there actaully was a couple of posts that went something like "Tha UOA on my mom's Cutlass ahd a lot less SI that the oil form my K&N track car"-type stuff. Just as many negative, as positive posts and a LOT of indeterminate stuff. I will probably stick with factory parts for now. I would be interested in saving money and better filtration with no airflow loss - I just don't trust any of the claims I've seen so far. remeber - I'm not racing and I have a new car. How many of the UOAs were done on rebuilt or other 'gearhead-type' cars? Look on top of your cabinets,door frames,anywhere dust settles. The primary component of dust is quartz - SI. just leaving an engine open to the air will introduce SI. Also, finding SI in UOAs tells us only one factor - we also would need to know the SIZE of those particles to determine the extent of the damage they could do.

 

we need REAL lab testing.

 

Carl

1 Lucky Texan

[Guest Legacy777]

If and when I do some engine work on my car, I'll take a look at the cylinder walls.

 

I've had k&n type filter on my car for probably 72k miles.

[Guest spagemurray]

Did you bother to actually read the UOA's at all? K & N = high SI. Racing yes, street use no.

[Guest 1 Lucky Texan]

If you have a specific page in mind please quote it..

I got tired of reading forum posts there as there was NO consensus. Maybe I missed the page you are refering too? I found Bobisthe....etc kinda hard to navigate. Maybe I'm just missing the good info?

 

Carl

1 Lucky Texan