K&N vs. Green Filter

[ZEN357]

So I have been running K&N air filter for years without even thinking about it. A couple days ago a friend recommended a new filter called Green Filter air filters. So I want everyone opinions on it. Below are the links to K&n Filters and Green Filters. Let me know your thoughts and opinions.

https://www.knfilters.com/default.aspx

https://greenfilter.com

 

[JMT]

What are you trying to gain with an air filter on a TJ? Our engines don’t get any noticeable HPgains through aftermarket air boxes and poor filters like K&N. Your doing more harm to your engine than anything letting so much debris in. Your best bet is a stock air box and a Fram Tough Gard filter. Really

 

[Chris]

The best filter you can run is a stock air filter. Or I believe @Jerry Bransford has mentioned AC Delco.

Those aftermarket filters don’t gain you anything except extra debris and contaminants in your engine. The only thing K&N is good at is marketing, period.

 

[tworley]

I'll stick with whatever paper filter I bought last time...fram maybe?

 

[Boinked]

My thought on these fancy air filters. If any of these high performance top of the line super special air filters were that good. The manufacturer would be installing them. Now maybe if you're building some 500-plus horsepower super Racing Engine. You might get a benefit and that's a big might.

As with anything in racing the company that pays the most money and gives away the most free parts gets their name on the car

 

[Chris]

As I also always like to point out, it's one thing to run a filter like this if you're strictly on-road. But on a Jeep, where you're taking it off-road, why would you want a filter that was going to let all that extra dirt and debris into your engine?

Remember, we're talking about an engine that has more in common with a tractor than it does a Ferrari.

 

[Jerry Bransford]

I'll stick with whatever paper filter I bought last time...fram maybe?

Fram makes good air filters too, I've actually seen them being tested with various micron-count lab "dirt" to test their efficiency. AC-Delco came in first in an ISO lab test for its ability to actually filter air while still providing good air flow, AC-Delco is my go-to air filter. Purolator makes good filters too.

Just say no to K&N.

 

[Brianj5600]

K&N filters have their place, but it isn't on a Jeep. Last time out the dirt was like brown flour. I'll take good filtration over 1/2 hp any day.

 

[BryanB]

After reading this thread I knew I had to make a change. The PO of my 04 Sahara had put in a K&N filter. I don't know if this is standard operating procedure for making this switch but the PO forced me to buy a replacement air box (see pic). My TJ now has a traditional paper filter and a replacement used air box.

 

[LJ Jesse]

I have a Green Filter that came with a supercharger kit. I held it up to the light and looked through it. It scared me off right away. I stuck with the stock airbox and a quality paper filter.

 

[mgroeger]

Question... the funky snorkel on the factory air box seems rather restrictive especially when it is angled to pint right at the hood. I understand it is that way to keep debris and water out while you are wheeling. What about popping that funky thing off for daily driving to allow more air flow?

 

[RubiconMike]

Question... the funky snorkel on the factory air box seems rather restrictive especially when it is angled to pint right at the hood. I understand it is that way to keep debris and water out while you are wheeling. What about popping that funky thing off for daily driving to allow more air flow?

I seem to remember someone did a dyno test of different "low restriction" air filters and taking the little snorkel off was one of their tests. If I remember correctly, they couldn't measure any difference. I don't think air restriction is a measurable problem with a stock 4.0.

EDIT: Found it: "We've been telling people to remove the air horn on the stock airbox for some power increase for some time now. Well, we tested that, too. It turns out that no power was made from that modification."

http://www.fourwheeler.com/how-to/engine/154-0706-jeep-wrangler-tj-intake-dyno/

Here is a later dyno test:
http://www.fourwheeler.com/how-to/engine/154-0804-jeep-wrangler-intake-shootout/

Comparison of Jeep air filters:
http://www.fourwheeler.com/product-reviews/154-0611-jeep-air-filter-upgrades/