http://www.bobistheoilguy.com/airfilter/airtest1.htm

 

IMO thats a worthy link!

"In my opinion, this means that if you are picking an air filter based on performance, you probably aren't doing your car any favors. For the record, the K&N was the best flowing filter. Of the 3 types of media tested, the cotton gauze type filters flow best."

I find that interesting. Mostly because it's been my gut instinct for some time. It's awsome that an enthusiast like us has actually measured the pressure drop.

"That said, both the cotton gauze type (K&N) and foam filters (Amsoil & Jackson Racing) showed the same levels of filtration. Both performed poorly compared to the fiberous or paper filters (Napa, Baldwin, and Mazda).
"

This has also been my opinion of the oil / gauze type. However there are two points I'd like to make.
1) To think that dirt getting by the filter is going to cause engine harm is very narrow minded. The egr system combinded with oil from the PCV system is far more likely to score cylinder walls, erode piston rings, and valve stems.

2) A larger filter (conical) will slow the air velocity per a given sq". And a conical tends to pull equally from around the perimeter. A flat panel may of may not pull equally across it's entire surface. Just depends on the shape of the passages feeding the box before the filter.

btw, I personally rebuild and hot rod engines. Some for myself and some for others. IMO with todays engines having such a tight piston to wall clearance.. and the improved air velocity in the heads.. cylinder wall scoring a thing of the past for mast engines I've tore down over the last 10 yrs.


Excellent link. Thanks!

Regards, Rich

 

Ok, just to continue the comparison. Plexiglass tubes were used to make smoke machines. Carbon resistors were used to generate the smoke. On one end of the tubes was the filter media, and there was a fan on the other end,
which was not needed. Just the convection air flow off the resistors (smoke went straight up to the filter media) was enough to see the difference. As
you can see from the third photo, the OEM paper filter media blocked the smoke, the smoke went right through the "oil" filter media on the K&N:

 

Much better testing, but did you oil the K&N so that it functions as it was meant to?

 

K&N FTW.

 

The K&N was brand new out of the box, and the instructions said it was pre-oiled.

 

I wanna see a video of this not pictures

 

I replace every 3rd oil change, so its about ever 12k... doesnt hurt

 

Sorry I don't own a video camera, I'm just into still photography.



I took several photos, here is another one a little later, that shows the same thing:

 

This also shows the OEM one creates alot of reistance to pull air in.

 

I'm impressed by this test Bob. It clearly shows that the K&N does indeed flow more, but that smoke will get through.
Next time I drive through a forest fire I will DEFINITELY use a paper filter. I would hate to ingest any smog or smoke into my engine. Now I just have to disable the EGR system, and my motor might last 50,000 miles!

 

This test says nothing about flow. The air flow is very low, just the convection from the resistor heating.

 

I'm not agreeing or disagreeing with anyone

I just want to understand Bob. Also how come you cant see any smoke in the tube of the left one?

 

fake! lol jk

 

It's there look at the left end of the resistors. And look directly above the resistors.

 

Wait wait everyone! look you can see the K & N one better baucse the smoke is contrasting better with the background.

The smoke with the oem one is almost the same colour as the background so you cant see it

 

There is no smoke over the OEM filter media.

I thought this was an interesting post from a Ford mechanic on FTF:

If a K&N gives you so much power, how much would you gain if you took out the filter all together? If it flows more air, that means the holes are bigger. Over 30 years of wrenching has shown me their claims are bogus. Replacing engines that have fine dirt in the intake passages, turbos that appear to have been operating in a sandblaster, valves that have little specks of silica sand imbedded in them. If I'm looking at a vehicle to purchase it, and it has a K&N in it, I'll shut the hood and look elsewhere.

 

When will I be encountering smoke from resisters? Silicon Valley?

 

Ok. So this latest in a series of pointless tests that prove nothing useful has shown us what? That smoke from a resistor can go through it? Great. Who cares. This is even less useful than spreading it all out in the driveway with a tape measure.

 

Now that I look at it the "K&N" material looks dry. When it is saturated in oil it turns a dark red and when it is dry it is light pink. I believe this test is fake. I'm sure Bob is doing what he can to fail the K&N filter and make is seem like he is right. I don't trust this test at all.

 

This last so called test, has a very serious flaw, & actually explains why a paper filter requires several times the area of gauze to flow an equal amount of air.

Your small area of paper has nowhere near the porosity as the same area of gauze. Of course the smoke won't pass through easily, or at all.

Try it again with 5.5 times the paper & show the results!

 

Interesting I would like to meet this guy.

I have worked on several engines Duramax Diesel's with K&N filters or other type filters you oil, and have never came across one that was like he described.

 

Can some one post up photos of a square foot of kevlar and then 12 square feet of cotton?

I want to prove that cotton will stop a bullet.

 

You guys are in what's called denial!! This is a brand new K&N filter right out of the box, and it said it was pre-oiled. Look at the original photos, the filter media was light pink right out of the box! Nothing has to be faked!

 

All this showed Matt is you have a $hitty camera........