K & N Air Filters

Hmmm the one on my tractor sort of looks like that. It's a clear glass/pyrex bowl, the wingnut on top. I don't recall any sort of dump port. I only clean it once a year, it's not that bad of a PITA.

The paper element housing does have a dump port. It's a black square rubber nipple at the bottom of the housing. The prefilter obviously helps though, I changed the paper filter 5 years ago and it still looks new

Some equipment also has a foam element precleaner that goes over the paper element. You're supposed to oil the foam precleaner, then wring out the excess oil. I suppose it saves the paper element, but it also means you have to clean the stupid thing quite often

Remember how for a long time small motors, like Briggs and Stratton lawnmower motors, had a block of oiled foam for an air cleaner? You had to frequently clean the foam - back then they recommended petrol - and reoil it

I have a 3 year old Honda lawnmower, and it has a paper element aircleaner. I use the air compresser to blow it out every fall, may have to change the element this year

 

I think you are making intuitive claim like I used to do regarding K&N.
K&N filters have been around for many years and used in racing circles, etc. K&N filters have been tested at 96-99% efficiency in filtration. How good is your OEM filters? Can you find data of it? Does Toyota tell you? No. Because they are not much better than K&N. Some OEM filters have been tested at 93% efficiency. Most good paper filters could be as high as 99%. K&N never claims to have better filtration efficiency of particles, it provides much better air flow thru the filters while maintaining good filtration efficiency.

 

I have been using one for about a year now, and have had no problems. Also have not noticed any increase in mileage. Just do not have to pay an outrageous price for the paper filter, the K & N cleans easily.

 

Evan,

I agree that a well designed filter can allow better flow and filtering ability with the same "size" filter. Amsoil's Ea air and oil filters are claimed to do that because of their "nanotechnology" filter media. However, K&N has not been shown to do that. My data on the subject comes from discussions over at BITOG. I have seen many oil analysis data with high silicon, and it was repeatedly traced to the use of K&N air filters. I have also discussed it with people that do oil analysis for a living. The opinion is consistant. K&N's allow better flow, but at the price of poorer filtration.

However, I will admit, that the long term impact of the poorer filtration is a big question. How much more wear will you see on a hundred thousand mile engine that used K&N vs a paper filter. I don't know what the difference would be. However, I generally keep my cars for a long time, so I choose the better filtration of a paper filter over the K&N.

As far as the statement regarding the use of a K&N filter for racing, I would say that racers have different goals than us daily drivers. They will quickly trade a bit of engine wear for increased performance. Thus, for a racer, a K&N filter is a no-brainer.

Hey, I went back over to BITOG and found this comparison of various filter types. While the test was not done by a professional lab, the guy seemed pretty meticulous. I think he confirmed the flow vs filtration claim.

Air Filtration Test

Again, picking an air filter is a personal choice. I choose paper, and at $7.50 a pop every 20-30k miles, it will not break my bank. I personally believe based on all that I have read, that K&N filters do not filter as well as a paper filter. However, it is very possible that the added wear caused by a K&N filter is negligable in the long run.

my .02

 

i have a k and n on my 01 prius, it really makes no difference to me, but its just nice that i could wash it and reuse it, thats about it

 

i have a k&n air filter on my 04 prius. it sounds a little better at full throttle but 0-60 times remain at 10 seconds. mpg was not affected

 

UOA in my 2001 Prius went from about 5 ppm Si to about 10 (10 k mile OCI), but actually long after changing to K&N air filter. Not accompanied by increased wear metals. I guess that if the Si doubled again, or if there was any hint of engine wear, I would revert to paper filters.

 

Where in the engine compartment is the air filter? Just wondering how easy it was to change it.

 

Open the hood and look for a black plastic rectangular assembly near the front of the car towards the passenger side. It has four metal clips securing the top to the bottom. Remove the clips and the top, and you will see the air filter.

However the dirty side of the filter is underneath. Remove the filter and look at how much dirt is on the filter. The normal test is to hold the filter up to the sun and see if light passes through. If not the filter should be replaced. I replace the filter at 15K mile intervals (the published schedule is 30K miles which in my view is optimistic.)

You can buy the correct Toyota replacement filter for $13 plus shipping from one of the Toyota dealers that sell discount parts over the web, for example:
DiscountToyotaParts

However, I note that this filter is listed for the 2004 - 2006 model years, so maybe the filter has changed slightly for subsequent years.

 

Only because I'm a cheapskate I wanted to point out that the K & N filter is priced at $32.22 at advance auto parts. While we find your parts, please enter your ZIP Code at PartsAmerica.com
and they are running a deal, buy online spend $25 or more and pick up in store get $5 off.
Advance Auto Parts - quality auto parts and accessories

Which would make the K & N $27.22 + tax. can't beat that for what you know will be new.

 

I bought a K&N for my '05 when it had about 60K miles. I turned 200K last night and have seen no ill effects from having the K&N installed. I say pick either one and keep up with the maint. intervals for it and you'll be fine.

Joe