Contour Enthusiasts Group Archives Forums Modifications Duratec Performance KKM + cold air induction?

Your numbers look good, so i guess K&N is doing a great job, for you. BUT...

50% more flow? That sounds like some crap off the K&N website. I'll need to see the tests...

Foam does deteriorate over time. But then so does cotton gauze. And i'd bet my bottom dollar the filtering efficiency of 2 stage foam trounces the gauze after 3 cleanings (the cotton woven fibers being unevenly laid out after a spirited wash.)

I have seen some testimony of burnt foam filters, but most were on carburated triumph cars with a wicked backfire and an over active pcv system (the filter being bathed in engine oil). I have yet to see a backfire on my car, so I'm not too concerned...

BTW, I would see fleet operators and rental car agencies using oil analysis to minimize maintenance costs. And I think we'll agree most of these vehicles see a spirited life with no special filters

I agree about the fleet use.

How many Duratec rental cars are out there. I would imagine most are Zetec...

The cotton/wire mesh straightens out the incoming air as opposed to the foams basically trying to stop it altogether (turbulence) this is where it makes a jump in CFM difference. Plus the air has less turbulence so it increases velocity and efficiency.

K&N has achieved over 99% efficincy rating. Like I said. You can fight over that last 1% all you like. Yes foam can hold more dirt. But the CFM rating of foam plummets extremely fast and it's pretty low to begin with (I gave specs in the Filter 101 post)

The CFM rating numbers were SAE.

K&N's numbers are a bit more skewed against foam & paper...

The test they showed had: (all indentical filter applications 12" round x 3.4" tall)

AMSOil LT-31 Foam: 376cfm
Dirty K&N: 463cfm (used 42k miles!)
Paper: 508cfm
clean K&N: 887cfm

That's like 236% more... That's seems pretty high. I'll stick with the 50% SAE numbers...

It would take quite a spirit washing to disrupt the layers of cotton and mesh to effect the filter efficiency greatly. (like compressed air! that's a no-no BTW)

Oh yeah. BTW - I've cleaned mine twice and those are my sample results. (matter of fact that sample was the oil change right after I cleaned it. When it is at it's worst efficiency) I live in KC. Probably slightly above average dust conditions.

I'm glad you like your foam. I like my CFM. I do not have a filtration problem. I am happy...

Fair enough.

But do check out the K&N vs Foam thread I started in this forum. More Hp out of 2 stage foam. Surprising to say the least...

Apples to oranges.
Comparing a stock panel filter type in a modified airbox. He never once tries a conical filter. (panle filters suck!) He also used a stock FIPK kit on a super charged engine. Imagine the piping being too small. :rolleyes:

We also do not know the testing parameters. (we all know how quickly the SVT heats up and drops HP on multiple runs) The runs looked pretty similiar across the board anyway...

Well, I figure both filters had a comparable area (its the same box, hey...) so that takes care of the 50% more flow from the K&N website...

There is alot we don't know about the test. But it confirmed that with equal surface, a two stage foam cone and a K&N cone would be very close in HP numbers.

The 50% better flow was SAE standards.

K&N showed the 236% improvement.

I've personally seen cotton gauss filters out perform foam. So I definitely believe the SAE numbers. I still think the K&N numbers where a best to worst scenario... I mentioned that in my previous post as well.

Panel and Conical filters are completely different animals all together!!! Not comparable to each other...

I use conical. Leave the panel to the OEM boys...

I mentioned that too...

I`d like to see the test results and the vacuum used to get the 50% difference. I would also like to see the filter brand used to represent the foam type. There is no way there is a 50% flow difference between amsoil 2 stage foam K&N. And here is proof :
http://www.fordmuscle.com/archives/2000/01/airfilters/index2.shtml

Try 7-10% difference. That I can believe...

K&N is full of it. Period. The 50% flow increase is calculated at 0.3 inches of H2O, and the numbers are extrapolated to 1.5 inches of H2O. You know what can happen when you extrapolate something that does not have linear behavior over a long interval...

So it all comes down to this. With equal area, K&N will give a maximum of 1 hp over foam on our cars. And that horse comes with inferior filtration. Pick your poison.

They said the K&N over the best foam or paper would show a 4+ HP increase on 300HP. So 3HP increase on 200HP (They mention the difference would be more noticeable on a high rpm motor. Which we have and DOHC to boot)

I know which one I choose...

Thanks for the good article...

Also you will note the the K&N shows noticeably less swirl than foam. This is also what helps it achieve the better HP numbers. (something I mentioned before )

My bad on the HP count. According to their tests, if we extrapolate, it would be roughly 3 hp for our cars. But we know what happens when we extrapolate...Plus small block V8 and Duratec, now that is apples to oranges...

Funny thing (I thought) is the best filter flow wise turns out to be Nascar glass medium paper made by none other than Wix. THAT was a surprise for me.

Now all we have to do is get Wix to make a poly glass filter for our car and we are all set...

If we extrapolate the price vs the HP gained from the change to the new filter we will end up with the following realization that we are...