cobrakraiger

Found this on a different site that I frequent
No K@N filters, ever.

I worked for race teams for years. One Toyota Atlantic team I worked on the driver thought the car was lossing power from the start of a race to the end. So we did leak down checks when we got the new engines in. 3% leak down- New. At the end of a race we checked it again and we got 29% leak down. So we sent the head to get the valves done and checked the leak down when the head returned. 4%- Leak down. At the end of the next race 31%- leak down. So we put three dabs of grease down stream of the air filter. "K&N" The next engine came in with 3%-leak down new. And at the end of the race 32%- leak down and the dabs of grease were full of grit. So we changed the filter to a oiled fome filter. 3%- leak down new and at the end of the next race? 18%-leak down. Better still not good. So we made a new air box and used a Mustang GT stock air filter. 3%-leak down new at the end of the next race? 1%- leak down yes I said "1%". The rings bed in and the engine seals up. We went from changing a engine at 300 miles with 29 to 34% leak down to. Changing the engine at 800 miles with 7% leak down.

So the bottom line is. You mite gain a little more power (1 to 2hp) but it will not last long and before you know it you will have a LOT less.
I work on 944s only and when I tear down a 944 engine that has had a K&N filter the cylinders have a LOT of scores from dirt that got through the filter.
If you dont beleve me do the grease test your self. Take out the filter and put a dab of grease in the air box. Then put your K&N filter in and dive the car for a few weeks and pull the filter out and check the dab of grease.

Good Luck Mike F



Quote:
"You are not alone. I too noticed the same thing on my former 98 Viper GTS. Alot of dirt seems to past threw the K&n's. This was during a complete breakdown of the engine. I no longer use K&N and stick with the stock filters...."


I was getting ready to put a K&N FIPK on my 2002 Z06 and someone showed me this. Has anyone else ever had anything like this happen? Now I'm a little nervous, I have always had a K&N FIPK on all my old cars but now I may get something else. Sorry if this is a repost,or if it is in the wrong section.

IM28702

I hit the dyno yesterday, and we found that my mass air was coated in oil from my K&N filters. From taking to the guy there, and my tuner, I am going back to paper....

WetteVette

Good info from someone with experience.

I heard just awhile back on this forum that the K&N flows more air, but the paper filter filters better.

Your data seems to verify that.

Mr.Bill

If your Mass Air had oil on it, It isn't the filters fault, It was over oiled, You have to be careful, The K&N filter system is a great system, But you do have to be careful. In the past I used K&N with a SC and have never had a prob, You want to make sure you use the K&N filter cleaning kit and do just as it says... Spray oil is the only way to go.

FUN LS1

NatB

I have several cars ( too many) - and some in the past with K&N Filters. I have reverted them all back to oem paper filters.

My current Z06 is completely stock except for a K&N Filter which came when purchased. More than likely I will get a paper oem ilter fo the Z06 too.

Here's my reasoning: The K&N add no real power and though supposedly last a lifetime must be kept clean and not over oiled.

OEM Paper filters changed regularly reportedly filter better and are cheap ( inexpensive).

So IMHO- why bother, stick with the paper elements and replaced once a year.

YMMV

ls1vette97

When cleaning my twin flow intake with k&n's i always find the oil residue inside the intake and all over the MAF! I barely use any oil as well... How much filtering is effected if you don't use the oil at all?

427435

If you care about your engine (or at least it's life), don't use the K&N or some other oil wetted filter----stick with the paper.

In another life, I was responsible for the engineering of off-highway vehicles including farm tractors. There isn't anything worse for dust than a tractor pulling an implement at 5 mph with a 5 mph tail wind !! Paper was the only filter that would keep those engines running.

Here's also a link to some "independent" testing on air filters. Although it was done with filters for a diesel PU engine, the principles and findings would be similar if they used filters for our cars.

http://www.duramax-diesel.com/spicer/index.htm

Edit: The whole report is well worth reading, but for those of you with attention deficit disorder , here's an interesting statement from the report:

"In 60 minutes the AC Filter accumulated 574gms of dirt and passed only 0.4gms. After only 24 minutes the K&N had accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt. See the data tables for a complete summary of these comparisons."

427435

You'll just be screening out the rocks !!

ls1vette97

Are there any good "cone style" paper filters? I dont think I've ever seen any honestly...

TexasMadMan

I've been planning on changing my K&N back to the OEM for the last 3 months. I'm doing it tomorrow. Anyone want to buy my used K&N cheap?

vettesmith02

NO

jacks996

too much oil and it goes through. not enough and you get dirt going through

Oh 2 Fun

Hmmm.....thanks for posting this. My car came with the K&N when I bought it. This makes me want to re-think my air filtration altogether.

cobrakraiger

Yeah anyone know of any? I really want to run some sort of a CAI on my car but I really don't want to risk the motor.

clayton1

Mine came with K&N too, Ive never been a big fan of k&n, never really trusted its filtering capabilities.
Ive been wanting to switch it out for sometime.
Thanks for the info..

blkdevl

you have to remember some of us have no choice but to use a k&n type filter in boosted applications. if there is a cone filter that is paper i would like to know it! i know HKS has foam filters that can meet some needs!

cobrakraiger

I have heard the foam ones are much worse than the K&N style becauses they come apart and can be sucked into the engine. I have no personal experience with foam filters, so this is all just stuff I have heard. I'm still trying to figure out what I want to do as far as a CAI

RonJ

An interesting read, for sure. Just more "bling"?

RonJ ...

Tom/99

Interesting info, thanks.