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Thinking of 'upgrading' your OEM air filter to a K&N? Think again...

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ace72ace

Zaino, I put that $hit on everything
1,242
71
Read this first;

http://www.svtperformance.com/forums/front-page-news-143/857223-svtperformance-2012-gt-k-n-replacement-filter-test.html

The K&N I had got 2nd hand is now in my wife's '11 GT. She'll never miss the HP, so don't tell. :-X
 
Wow, that does seem strange, isnt the Ford racing filter basically a K&N? Hard to believe there would be a 4hp/tq LOSS with the K&N. Damn, do I put my stock unit back in???????
 
There were issues with K&N in Evos too, they spun the air the opposite direction of the turbo because they didn't test it on the car and instead just made their generic one line up.
 
FWIW Ford runs K&N drop in air filters in the Boss 302R race car. When I asked about it they popped open the cover and there was the K&N. That's not an endorsement just a data point.
 
I recall rumors that they come over-oiled and it takes a bit of use before they dry enough to allow max flow. But I never saw proof either way.
 

BLAZN BOSS

Just went to the K&N web site............I'm gonna forward this report above and see what they have to say. They report HP increase. http://www.knfilters.com/search/product.aspx?Prod=33-2431
 
5 DOT 0 said:
FWIW Ford runs K&N drop in air filters in the Boss 302R race car. When I asked about it they popped open the cover and there was the K&N. That's not an endorsement just a data point.

That's a good data point, but if the cars are restricted, that K&N isn't helping or hurting IMO.

Jimmy
 

Sesshomurai

I have a silly question. So the car is sitting stationary on the dyno right? Exactly what kind of flow is expected through the air filter compared to actually moving down the road?
Or does the dyno provide that too?

EDIT: Nevermind, I see further down in the article how they addressed that.
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
I did this test on my car when I first got it and the K&N was worth 5hp from about 5500 to 5600rpm vs. stock. Not a huge difference, but it was something.
 
CaliMR said:
I recall rumors that they come over-oiled and it takes a bit of use before they dry enough to allow max flow. But I never saw proof either way.

I was thinking that, straight out of the wrapper they are pretty moist. I wipe mine down before install to get any excess off. Who knows, I think I'll leave mine in for now. I would really like to hear K&Ns response.
 
1,255
2
GA
The K&N filter came with my Ford Racing Power Pack. I have had no noticeable issues. The car has plenty of power on tap (so much that my wheel hop got much worse). The wheel hop is probably from the tune though, since FR claims it increased the low end torque by 60 ft-lbs at 1500 RPM.
 
Your not going to feel any power difference between a stock or k&n filter. the k&n will help with dust being the oil will help catch stuff but remember the k&n can very easy be over oiled and that will hurt for sure. I found with the hayabusa that sure the k&n was a bit and I mean a tiny bit less hp but it caught way more dust then any stock filter.
 

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