K&N Air Filter gets my thumbs up

[irollturbo]

This past weekend I did some back to back test of a K&N and an Amsoil Foam air filter in my Volvo S70 Turbo. After reading posts and articles on various web sites I had switched from the K&N to the Amsoil due to dirt concerns. I ran the Amsoil filter for a year or two. But I never was really happy with the way the car ran with it. But I shrugged it off.

So this past weekend I decided to test the two back to back and have the following observations:

-Maximum turbo boost pressure seems to be 1-2lbs higher with the K&N per boost gauge.

-Throttle response is much better with the K&N. The car almost felt like it had a slight hesitation with foam. With the K&N it responds to throttle inputs and downshifts more readily.

-0-60 time is probably the same per gTech. 0-60 uses only first and second gears which are both boost limited.

-Gas mileage seems a little better with the K&N. I have not measured exactly, but with the K&N my fuel economy is climbing according to my average gas mileage reading.

For filtering ability I'll have to wait for an oil analysis over the next year or so. However, after reading Anthony's observations I am less concerned about the K&N's ability to filter versus the foam.

I am neither a K&N nor Amsoil bigot. I could hardly care less which brand filter comes out on top. I own both already and just want to figure out what works best for me. After experimenting with both filters, I like the way the K&N runs in my car better and it is very noticeable to me. I realize others may have different experiences in different cars.

I think that some people's claims that the K&N does nothing and is a waste of money is a bit unfair. I feel a difference. In addition, I think claims that foam air filters are the perfect filters are a bit overly enthusiastic.

 

[kevm14]

Perhaps the filter on that car is undersized.

Still, why don't you get yourself an OEM Volvo filter and compare that?

 

[T-Keith]

The studies I've seen don't really show the Amsoil filter flowing better then the K&N. Try a paper filter and see what it's like.

 

[irollturbo]

quote:

---

Originally posted by kevm14:
Perhaps the filter on that car is undersized.

Still, why don't you get yourself an OEM Volvo filter and compare that?

---

I had tried a compare to the stock paper a couple years ago. The K&N still felt snappier than the paper.

I've read the studies too, but it is not consistent with what I feel.

 

[irollturbo]

Being ever the tinkerer, I put in the Amsoil back in for now. I want to complete my current 6 month interval and do the oil analysis. I don't think a couple hundred miles on the K&N is going to affect this.

After I get the results back I'll decide what to do for the next 6 months.

I also put a new set of plugs in the turbo and will see if the throttle response is improved with the Amsoil air filter. My enhanced ECU program tends to be hard on the plugs even after only 5K miles.

 

[oilcan]

K&Ns I agree flow more air thats why so many race teams use them. I ran K&Ns for several years in different trucks. It wasn't until my wife's Dodge Dakota I was putting in spark plugs @ 30K when I removed the airbox the throttle body was just loaded with dirt and grime. I ended up pulling the throttle
body to clean it completely. That ended my use of K&N Filters.
I run an Airaid on her new Trailblazer with 20K I have not seen the dirt or grime.
I run paper with a dry foam pre-fliter on my modified 460 in my 86 F250 4x4. The 4160 Holley is as clean as when I installed it 1.5 years ago. I ran a K&N on this truck before doing mods and the 4180 Holley was never as clean as the 4160 Holley is. Performance and Gas Mileage is unchanged.

 

[TC]

After coming across a K&N display at Pep Boys last year, I took one out of its box and held it up against the store's overhead fluorescent lights. If I were an astonomy buff like my brother, I'd say it a very pleasing "star effect" like the night sky one sees while traveling through the desert. But the technical term for this is "holes." And holes -- big ol' sand grained-sized holes -- don't help filtration much, confirmed by silicon levels in many K&N UOAs. Unless it was a track car, I'd never consider putting a K&N in my ride.

 

[irollturbo]

With new plugs and the Amsoil foam back in, throttle response with the foam is better than it was when I had the foam in before. However, I am still losing 1-2psi of turbo boost compared to the K&N. This is huge. It seems I am not the only one to experience a performance loss moving from K&N to foam.

Check out: http://neptune.spacebears.com/cars/racing/rd990702.html

They said:

"We yanked the over-oiled Amsoil filter and put the K&N filter in its place. Amazingly, this helped a lot. We immediately saw 292.9 hp, a four horsepower gain over the Amsoil's best pull. Not bad for a filter. K&N, we're convinced. "


I am thinking of replacing my air filter with a block of wood. I figure that if I can block all airflow then I will block all possible dirt contamination as well.

[ March 22, 2005, 01:18 AM: Message edited by: irollturbo ]

 

[LVHospiceRN]

quote:

---

Originally posted by irollturbo:
With new plugs and the Amsoil foam back in, throttle response with the foam is better than it was when I had the foam in before. However, I am still losing 1-2psi of turbo boost compared to the K&N. This is huge. It seems I am not the only one to experience a performance loss moving from K&N to foam.

Check out: http://neptune.spacebears.com/cars/racing/rd990702.html

They said:

"We yanked the over-oiled Amsoil filter and put the K&N filter in its place. Amazingly, this helped a lot. We immediately saw 292.9 hp, a four horsepower gain over the Amsoil's best pull. Not bad for a filter. K&N, we're convinced. "


I am thinking of replacing my air filter with a block of wood. I figure that if I can block all airflow then I will block all possible dirt contamination as well.

---

While the dyno may have showed a 4 hp gain, i doubt if anyones "butt dyno" could identify that little of a difference...the mind is a powerful thing..

As someone else had said, if your engine intake is restrictive, a freer flowing air filter MAY help...why not take the air filter out and see if the throttle response is different?

darrell
sin city

 

[GT Mike]

4 HP is less than the margin of error on the dyno, and unless you're mowing grass, close to undetectable by even the most discerning person. It most likely did nothing to affect the HP.


Edit: I took a look at that website...What was not mentioned earlier in this thread is that the K&N produced only 1.5 HP more than the stock airbox, and when the aftermarket airbox was first installed with an Amsoil filter in place, the car actually lost power! Swapping in the K&N only barely made it past the baseline pulls on the car as it sat box stock!

[ April 10, 2005, 02:52 PM: Message edited by: GT Mike ]

 

[metroplex]

Paper filters are designed to FILTER harmful particles.

KN filters just let everything through. Don't go by the $20 oil analysis and believe that because they did not pick up "dirt" that it isn't already ground into your rotating assemblies.

I drove through a dusty cornfield with a KN filter and opened the box to find hardly any dirt in there. I went back with a paper filter and tapped out the Sahara desert.

 

[Flashlightboy]

I feel a little sheepish posting this but I am a K&N believer and installed one on my Craftsman 6.5 HP B&S mower. I've taken it off and examined it a few times - cooties on the outside but nothing observable past the filter.

I can't think of much more of an urban test than flying dirt and grass inches above the ground.

 

[Ken2]

iroll,
If you can, try a Mann pleated paper air filter in your Volvo. Mann is the OEM supplier, and I've found my upper air box and throttle body cleaner with the Mann filter than with the K&N. The turbo boost gauge seems to climb as fast and the car's acceleration seems as quick.


Ken

[ April 18, 2005, 05:47 PM: Message edited by: Ken2 ]

 

[Herfnerd]

quote:

---

Originally posted by irollturbo:


For filtering ability I'll have to wait for an oil analysis over the next year or so. .

---

Maybe its just me, but I don't see how performing an oil analysis will help you determine if the air filter is efficient or not.

You will see an increase in hp and fuel mileage because the filter is free flowing. But the efficiency is also so low that excessive amounts of contaminants will be constantly ingested.

I dunno if a negligible 4 hp gain is worth it. However, its JMHO and YMMV.........

 

[Eli89SHO]

I installed a K&N on my 89 SHO and it was much better than the paper filter. Better construction than the paper filter, sturdier. Also, it made my throttle snappier. I also installed a larger MAF at the same time so that could account for the extra,, extra snappyness.

 

[Ugly3]

Trading dirt for an extra 1/2 HP is not a good deal to me.

 

[04.SPT.WRX]

Are there any definitive tests to show which filters better? I have yet to find one. This seems to be quite a polarizing issue.

I am currently using a K&N in my WRX – it seems to work quite nicely. Turbocharged engines seem to be more sensitive to restrictions placed before and after the turbo in terms of power produced; more so than normally aspirated (freer flowing exhausts can reduce power in NA). Over the past year, starting from stock I have slowly added less restrictive components pre and post turbo with very good results. More power and better fuel mileage (2-4mpg worth).

I did just get a UOA a bit high in Si, possibly due to the silicon in the K&N oil. I think I’ll give it one more drain interval and submit another UOA to see any trends developing.

Bill

[ May 01, 2005, 07:25 PM: Message edited by: 04.SPT.WRX ]

 

[Huhwhye]

Since finding this forum I have removed all my K&N's and went to paper or foam depending on the application.

I did the sunlight test on a K&N that I removed. That's all the proof I need. How's a 1/16" of cottom gauge you can see sunlight thru supposed to protect your engine?

 

[TallPaul]

I had a fine UOA using a K$N that had been in place maybe 15,000 miles. But I have switched back to paper because it is too much a pain in the neck to clean and re-oil these things.

 

[surfstar]

I use a Ractive cone filter, which is the same elements as a K&N and have cleaned/re-oiled it once (w/ K&N oil). I probably over oiled it, actually. My UOA after 4500 miles on an engine with 150k miles showed 5ppm of Si. No problems on the air filtration end and I have a cold-air setup which flows better than stock and picks up air closer to the bottom of the engine bay, nearer to the ground. I'm not worried, and enjoy the performance and MPG increase with the K&N.

http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=001904