Air filter study

[Q45tech]

http://home.usadatanet.net/~jb...R.htm

"In 60 minutes the AC Filter accumulated 574gms of dirt and passed only 0.4gms. After only 24 minutes the K&N had accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt. See the data tables for a complete summary of these comparisons.

These tests were with drop in filters so cone would be worse.

[maxnix]

Ah, but the cone sounds so kewl!

Thanks for real world information.

Interesting to note that "super brands" Amsoil and Baldwin were about as bad as K&N.

[CrimsonQ]

Confirms my suspicions all along

Had a k&n filter on my 98 cobra for about 2 weeks before I noticed "problems".

Id never own another K&N filter again.

[silentfurymm]

I knew before hand that the K&N's or reusable filters in general where far less efficent than paper. On the other hand the sound and marginally better gas milage where enough for me me to be fine with it, especialy on the old Mx6. Most of the time when people have problems after installing a K&N its not because of lack of filtering, its due to excessive oil from the element coming off and coating your MAF sensor. Consiquently hindering its performance greatly and eventually sending the ECU into a limp mode.

[PopPop]

Ah, but the cone sounds so kewl!

Thanks for real world information.

Interesting to note that "super brands" Amsoil and Baldwin were about as bad as K&N.

The sound that the stillen filter makes definitely makes the engine sound stronger and deeper toned! Do you notice a lost of bottom end performance with the cone set-up? I notice like it's drawing in too much air if you punch it from take off like its too much air for the MAF to handle from a dead start! If you punch it while your at cruising speeds the motor seems to benefit from the cone set-up! Does the oil attract more dirt particles which in turn will cause the MAF and TB to accumulate more dirt? With the drop in filter it seems like there's no low-end power lost! May be larger MAF with cone style filter set-up would make more low end HP/Torque! Anyone have source that makes a larger than 95mm MAF?

[Q45tech]

If you read the graphs you will see the pressure differentials are so minor from even the worst to best at 350 cfm [~~ 310-330 HP], 4.54-6.23 inches of water column that say 1.7" spread or roughly <0.5%. At the more normialized lesser flow of a Q the spread is even less.

Years ago post some similiar measurements trying oem vs K&N vs NO filter at all in stock air box..............................................at 6,000 rpm under road load the numbers were very very similiar ~~~1.5" W.C. max difference.

Anyway at 60 mph [2000 rpm] the cfm drops to ~20-25 [around 25 HP] so how could any filter effect highway mileage.

Might be interesting to weigh used oem filters to see how much dust you really collect in driving 15,000-30,000 miles..........weigh brand new and periodically.

[Falkdesigns]

And yet, I've never seen a car, truck or bike that races on dirt use anything BUT an oiled air filter. Including endurance races, such as the Dakar rally (15 days of the most grueling race conditions on Earth) where they're out there in dirt, dust and sand racing all day long. Maybe the dirt that passes has a performance boosting element. Chrysler offers a "Mopar" (K&N) air filter that does not affect warranty. Still, with these cars in particular, there's a special circumstance with the MAF being directly behind the filter box. I see no benefit to using one in the Q45, but you can't argue the dyno proven gains in other cars.

[elwesso]

And yet, I've never seen a car, truck or bike that races on dirt use anything BUT an oiled air filter. Including endurance races, such as the Dakar rally (15 days of the most grueling race conditions on Earth) where they're out there in dirt, dust and sand racing all day long. Maybe the dirt that passes has a performance boosting element. Chrysler offers a "Mopar" (K&N) air filter that does not affect warranty. Still, with these cars in particular, there's a special circumstance with the MAF being directly behind the filter box. I see no benefit to using one in the Q45, but you can't argue the dyno proven gains in other cars.

They also arent factoring in longevity... To each their own.

[Falkdesigns]

Honestly, in all seriousness, I've been "modding" cars since 1988, I've known sooooooo many people that use K&N, or other various brand of oiled air filter, and NEVER have I seen a single one of them cause some early engine death like some would like you to believe on here. Not once, never. That factors in longevity.

[maxnix]

Honestly, in all seriousness, I've been "modding" cars since 1988, I've known sooooooo many people that use K&N, or other various brand of oiled air filter, and NEVER have I seen a single one of them cause some early engine death like some would like you to believe on here. Not once, never. That factors in longevity.

Standards vary, and race engines are constantly rebuilt. The question is not so much early death, but performance at later engine life. Quantitive data in a controlled environment don't lie. More dirt = more wear.

But the cones sure sound kewl!

[silentfurymm]

Honestly, in all seriousness, I've been "modding" cars since 1988, I've known sooooooo many people that use K&N, or other various brand of oiled air filter, and NEVER have I seen a single one of them cause some early engine death like some would like you to believe on here. Not once, never. That factors in longevity.

Pretty much my experience. Those that do have problems are usually related to whatever is used to oil the element by whoever manfactured it (K&N, AEM, Greddy, etc) messing with the MAF. For some reason GM cars seem to be particulary susceptable.

As far as gas milage, both my father and myself track our mpg maticulously. Before the Cone filter went on my Mazda Mx6 I consistently got 27mpg on the highway, afterwards it was 29. When we put a drop in K&N in the Q45 back when it was still my fathers he observed an increase in highway mpg from 21 to 23.

[Falkdesigns]

Sound's got nothing to do with it

And I for one, have no intention of ever in my life owning a car for 15 years and 500k. In 20 years driving and owning cars, I've never had one for more than 4 years (though I plan to keep my Q45 for 5), and anyone who buys a car from me can rest assured that it's been meticulously maintained, loved and cared for better than 99.5% of the rest. That's why I have always gotten high dollar values for my cars when it's time to sell them.

[Q45tech]

"no intention of ever in my life owning a car for 15 years and 500k"

We have a customer [still has Ls400 and Sc400 wife/ daughter] who had a 90Q and finally traded it in with 275,000 miles. [needed an engine and transmission].........over the last year he has had 3 different OTHER cars..............current daily driver is a Jag.

He wants to find another 90 Q and start over............nothing satisfies like a 90Q even though it costs almost as much as a new one to own and drive.

He had every suspension , engine ecu/tcu mod available, new seats, quality repaint, 16" wheels...........it was pretty cherry.

[maxnix]

"no intention of ever in my life owning a car for 15 years and 500k"

My family owned a BMW 2800CSa for 32 years. Only about 120K on it, though. It was that cool of a car. Either had to restore it or sell it, and we didn't need another car at that point and had no room for it.

[texasoil]

Grew up on a rice farm in south Louisiana. LOTS of first hand experience operating engines in extremely dusty conditions. Saw and experienced first hand the impact of air firtration on engine life.IT is EXTREMELY VITAL to engine life. Catepillar showed that feeding an engine as little as 1 tablespoon of dust into the engine over an an 8 hour period--and the engine is worn out!!! after that 8 hours. Piston rings,pistons, cylinders, bearings, crank shaft--worn out!!!.

Used to be farm equipment had 'oil bath' air cleaners--big ones. One diesel tractor had one 18" in dia and nearly 3 feet tall--crammed full of 'trays' llike a distillation tower--and in dusty conditions we had to clean it every day--the oil would get full of dirt so that it was mostly soil and little oil left. It was Normal to overhaul that engine every 3 years (about 1000 hours), replacing cylinders, pistons, rings, bottom end bearings. Then 'dry air cleaners' were developed (paper filter with centrifugal pre-cleaners.) The 'pre-cleaner' had a clear plastic bowl that held about 1 quart of dirt, and sometimes we had to stop and empty it every hour!. The pleated paper main filter had a pressure drop indicator so you could see it load up. Every day we took it out and 'rapped it' and got a handfullof real fine dirt. Inside stayed pristine. Engine life went to? We never again had to overhaul engines! We had some with over 12,000 operating hours and they still had new compression, new oil consumption, new oil pressure. Of course the oils had improved during this time, Diesel fuel and propane had not changed though. Air filtration was the key!.

Oil bath air filters are lousy compared to properly sized/designed dry pleated paper filters. If you want maximum PERFORMANCE--then all you want is a 'gravel catcher' screen. If you want engine life--run the OEM pleated paper filter with a known high quality element.

[elwesso]

Interesting information, Keith... Thanks for sharing..

Assuming that the engines were the same with the oil filter vs the paper filter, did you notice any difference in engine performance?

[Q45tech]

There CANNOT be any difference in performance unless the filter offers any MEASURABLE SIGNIFICANT DIFFERENCE IN RESISTANCE.

To some 1/4%-1/2% difference is significant..........but to me 1.0 HP is in the measurement noise.

This arguement will go on forever as long a oiles/cone filter manufacturers spend money to advertise mistruths and support teams.

People just want to believe that they can out do the factory with simple cheap mods. Why no graduate automotive engineers ever set foot on forums.........they would throw up after reading peoples posts then run away screaming.

Same with tire/wheel forums where experts [testimony] are dished and ignored because their recommendations cost more money.

[DrewQ45]

Honestly, in all seriousness, I've been "modding" cars since 1988, I've known sooooooo many people that use K&N, or other various brand of oiled air filter, and NEVER have I seen a single one of them cause some early engine death like some would like you to believe on here. Not once, never. That factors in longevity.

I ran a K&N filter for two or three years in my Q without any problems whatsoever, however, I switched back to dealer filter for the past few.

Tech's arguments that the dealer filter, the amount of pleats, filtration levels etc. convinced me that OEM is a better filter but I do not believe for a minute that oil is extracted from the filter to be deposited anywhere else. The filter's large area along with the amount of air passing through is just not enough force to lift oil particles. The K&N filter probably sees small horsepower gains because it filter's less, possibly allowing more air flow. Of course there are down sides to this..it's a give and take. I don't believe engines are being damaged by K&N filters but in the very long run, it might make a difference to go with the OEM and change often. As to the K&N being used offroad...well it makes sense. They are rugged wire framed filters that can be knocked off/wash n oiled...then used again and again. IMHO and they probably don't clog as easily as the paper filters either...

For gentle driving in the real world...I'll just stick with OEM.

Drew

[Q45tech]

they probably don't clog as easily as the paper filters either...

Look at the graphs they clog faster because their area is smaller: few pleats and less depth on oiled units

Simple just iron them flat and measure the resulting AREA.

Clean a K&N of oil then hold it up to a strong light source.........you will see how the dirt particles get thru.

Obviously few think of 150K life until they get close to 150k, by then it's to late to heal.

I see too many blue smoking Q to be objective concerning a 1 HP gain.

[elwesso]

And now we've made a complete loop....

IM still convinced that most people think they do more simply because they are louder....

[Ozzie]

or an OEM filter and box is unavailable...........

<-----------------

(and it does sound cooler!!!!)

[Ezekial]

i would run an air box if i could find one with a 5" feed and if i had room between the headlight and the turbo

[maxnix]

i would run an air box if i could find one with a 5" feed and if i had room between the headlight and the turbo

Two OEM boxes ought to do it.

[chinaonnitrous]

an agressivly oiled K&N filter will pull oil into the maf.

Ive done it. Period.

[maxnix]

an agressivly oiled K&N filter will pull oil into the maf.

Ive done it. Period.

You know, when I change my OEM filters every 12K miles, I am amazed how much tar and road oil there is trapped in them. I can't imagine any benefit from adding more oil to it.

[nuQ]

^^^^^AGREED

[FarFetched]

I'd say just put a SAFARI snorkel system on a Q and be done with it

It keeps cold air comming in, you can cross deep waters w/o killing the engine and most of all it keeps the "dreaded" dust/dirt away .And of course keep OEM air box intact with OEM air filter element!I'll say SAFARI SNORKEL -

[Ezekial]

Two OEM boxes ought to do it.

thank god i have no room for that

alloy mesh in front of turbo then air conditioner filter material (if you want the best)

[elwesso]

You know, when I change my OEM filters every 12K miles, I am amazed how much tar and road oil there is trapped in them. I can't imagine any benefit from adding more oil to it.

Yeah.. This past year I went about 3-4 months over my normal change interval... Once it starts getting dirty, it gets even dirtier fast... I dont understand why they had replacement every 30k! The filters had to be completely gummed to nothing.

[maxnix]

thank god i have no room for that

alloy mesh in front of turbo then air conditioner filter material (if you want the best)

Are we talking 20"x30" Filtrete UltraAllergen? That might be as good as two OEM for a couple of months.

Iron out the filter material to compare area. Read filter specifications (and test like by Q45tech) to see maximum particle size pass through. A manometer downstream will give you a good idea of filter load.
Modified by maxnix at 2:00 PM 4/25/2006