I know K&N gets bashed around here, that's fine, but has anyone ever perform the "white glove" test with OE filter? Since OE filter is not 100% efficient, who's to say the white glove won't find traces of dirt upstream of the filter?
Are K&N drop ins still bad at filtering?
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When the engine failed in my 04 below due to a stuck oil pump bypass the cross hatching on the cylinder walls was still visible and the was no perceptible ridge.
About 245 of the 250k miles on the engine were with the same k&n filter serviced about every 50k
About 245 of the 250k miles on the engine were with the same k&n filter serviced about every 50k
One instance of a K&N not causing damage proves nothing.
Environmental dust varies widely with location.
Back in the day some racers in damp places like parts of England went with no filter.
Nothing like the sight and sound of a row of Webers open to the world.
Environmental dust varies widely with location.
Back in the day some racers in damp places like parts of England went with no filter.
Nothing like the sight and sound of a row of Webers open to the world.
Is that sarcasm or did it sound really good?
I think the problems arise when they are not oiled correctly. It's very easy to over-oil them and thus contaminate your MAF sensor. I've used them on BMW'a, Hyundai and Harleys and have never had a problem but I am careful about removing any excess oil which is always on there after you spray it.
I had one in my V-6 Challenger which is now my son's car. It seemed to make a slight difference when I first stepped on the gas. Was a little more responsive. I had planned to leave it in and forget about it. I hear they won't need cleaned for 60-80,000 miles (depending on your conditions of course). I specifically checked the intake for dust in the tube when I did the last servicing and there was none.
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Originally Posted By: mcrn
Originally Posted By: Jimzz
Nope they are still junk and worthless. Please don't waste your money or time with them.
If they did half do what they claim OEMs would install them at the factory.
Im sure if they were as good as they claim....Porsche, Ferrari, Audi etc would have them stock. I am not saying they cause engine failures but why put them in a stock car that it can only hurt? Nothing to gain on a stock car.
I think I read that Lamborghini uses K&N as a STOCK air filter
Originally Posted By: Jimzz
Nope they are still junk and worthless. Please don't waste your money or time with them.
If they did half do what they claim OEMs would install them at the factory.
Im sure if they were as good as they claim....Porsche, Ferrari, Audi etc would have them stock. I am not saying they cause engine failures but why put them in a stock car that it can only hurt? Nothing to gain on a stock car.
I think I read that Lamborghini uses K&N as a STOCK air filter
Originally Posted By: Hessam
Originally Posted By: 04SE
Originally Posted By: Shannow
Originally Posted By: Hessam
they are not worthless... if you don't drive on dirt roads, and keep most of your driving to paved street/highways, they will filter fine. Their filtering efficiency actually improves with time.
I got one in my LX450 since about 119K miles, and my engine is doing fine. no problems whatsover, and i have never even replaced or cleaned it... it's getting about time I do something about, and thinking about going back the OEM paper filter, but I am not sure I am ready to give up my 16 mpg that I get with my K&N
How does the K and N improve your fuel economy ?
I'm assuming that you are driving at normal highway speeds, and the the throttle plate is mostly closed for nearly all of that, so then how can the K and N possible give better economy, when it's the overall restriction between air intake and inlet valve that controls your airflow/load ?
Doesn't add up.
Because a multi-million dollar advertising campaign says so? Along with fancy graphs and 'estimated' HP/TQ increases.
No because I actually measure my MPG for every tank of gas. My average has been 16.2 with the K&N filter with about 75% highway and 25% city driving. with my old OEM filter my average was 15.1 and the highest tank I ever got was 15.8.
The K&N can have an increase in MPG in some engines. They engines they work on best are the old school engines, without a lot of modernized computerized management. To best of my knowledge even though the LX450 does had fuel injection, it's a very basic FI set-up and the main block is essentially an old Buick I6 from the 60's which had been used in most landcruisers until the mid 90's.
So if I understand you correctly you are saying that with an oiled gauze filter you've increased your mpg by 1 mile over the stock paper element.
What utter nonsense.
For starters on a stock engine the oem intakes aren't restrictive. Unless the engine is modified such as heads,cam and exhaust the stock intake isn't isn't anywhere near its peak cfm,and unless the engine is being operated at high rpm there isn't any chance the airflow is inadequate.
And an intakes design is centered around air velocity. So a small engine with a huge intake volume has the air travelling at low velocity and that actually makes the engine work harder to suck. A smaller intake will increase the velocity of air travelling which reduces the resistance and increases volumetric efficiency.
Intakes and exhaust are a balancing act. If the intake is too big part throttle response will suffer.
Anyways believing the filter increased your mileage by 1 mpg is nonsense.
A headwind has more effect.
Originally Posted By: 04SE
Originally Posted By: Shannow
Originally Posted By: Hessam
they are not worthless... if you don't drive on dirt roads, and keep most of your driving to paved street/highways, they will filter fine. Their filtering efficiency actually improves with time.
I got one in my LX450 since about 119K miles, and my engine is doing fine. no problems whatsover, and i have never even replaced or cleaned it... it's getting about time I do something about, and thinking about going back the OEM paper filter, but I am not sure I am ready to give up my 16 mpg that I get with my K&N
How does the K and N improve your fuel economy ?
I'm assuming that you are driving at normal highway speeds, and the the throttle plate is mostly closed for nearly all of that, so then how can the K and N possible give better economy, when it's the overall restriction between air intake and inlet valve that controls your airflow/load ?
Doesn't add up.
Because a multi-million dollar advertising campaign says so? Along with fancy graphs and 'estimated' HP/TQ increases.
No because I actually measure my MPG for every tank of gas. My average has been 16.2 with the K&N filter with about 75% highway and 25% city driving. with my old OEM filter my average was 15.1 and the highest tank I ever got was 15.8.
The K&N can have an increase in MPG in some engines. They engines they work on best are the old school engines, without a lot of modernized computerized management. To best of my knowledge even though the LX450 does had fuel injection, it's a very basic FI set-up and the main block is essentially an old Buick I6 from the 60's which had been used in most landcruisers until the mid 90's.
So if I understand you correctly you are saying that with an oiled gauze filter you've increased your mpg by 1 mile over the stock paper element.
What utter nonsense.
For starters on a stock engine the oem intakes aren't restrictive. Unless the engine is modified such as heads,cam and exhaust the stock intake isn't isn't anywhere near its peak cfm,and unless the engine is being operated at high rpm there isn't any chance the airflow is inadequate.
And an intakes design is centered around air velocity. So a small engine with a huge intake volume has the air travelling at low velocity and that actually makes the engine work harder to suck. A smaller intake will increase the velocity of air travelling which reduces the resistance and increases volumetric efficiency.
Intakes and exhaust are a balancing act. If the intake is too big part throttle response will suffer.
Anyways believing the filter increased your mileage by 1 mpg is nonsense.
A headwind has more effect.
agree with Clevy.
in fuel injected engines, once an engine is in closed loop operation, it gives the same amount of fuel for a given amount of air, regardless of where the restrictions are upstream, i.e., the throttle plate vs the filter vs the plumbing. IF a filter is very restrictive, equal power output would require less restriction at the throttle. the resulting air volume and manifold pressure would still be the same, and the ecu would match that with the same amount of fuel.
In a carb'd engine, yes a restrictive filter could hamper mpg. The marketing department is still selling it...
The pumping losses argument doesn't hold water either, as the filter is in series with the throttle plate, so again a different filter is merely offset by adjusted throttle position to maintain the equivalent air volume and fuel mix. the engine still sees the same manifold pressure during intake, and same backpressure during exh strokes.
in fuel injected engines, once an engine is in closed loop operation, it gives the same amount of fuel for a given amount of air, regardless of where the restrictions are upstream, i.e., the throttle plate vs the filter vs the plumbing. IF a filter is very restrictive, equal power output would require less restriction at the throttle. the resulting air volume and manifold pressure would still be the same, and the ecu would match that with the same amount of fuel.
In a carb'd engine, yes a restrictive filter could hamper mpg. The marketing department is still selling it...
The pumping losses argument doesn't hold water either, as the filter is in series with the throttle plate, so again a different filter is merely offset by adjusted throttle position to maintain the equivalent air volume and fuel mix. the engine still sees the same manifold pressure during intake, and same backpressure during exh strokes.
Even in most carbureted engines the float bowl is vented to the clean side of the air intake, so pressure drop across the filter and induction plumbing is compensated for.
A government study showed that even on older cars air filter restriction didn't greatly affect mpg, even when pressure drop was enough to deform the filter:
https://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf
A government study showed that even on older cars air filter restriction didn't greatly affect mpg, even when pressure drop was enough to deform the filter:
https://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf
Originally Posted By: circuitsmith
Even in most carbureted engines the float bowl is vented to the clean side of the air intake, so pressure drop across the filter and induction plumbing is compensated for.
A government study showed that even on older cars air filter restriction didn't greatly affect mpg, even when pressure drop was enough to deform the filter:
https://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf
Interesting.
Thanks for posting
Even in most carbureted engines the float bowl is vented to the clean side of the air intake, so pressure drop across the filter and induction plumbing is compensated for.
A government study showed that even on older cars air filter restriction didn't greatly affect mpg, even when pressure drop was enough to deform the filter:
https://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf
Interesting.
Thanks for posting
I tried them years ago on a 98 Mustang and a 98 Neon. As far as I was concerned K&N let lots of dirt into the engine and left an oily mess all over the MAF. I didn't over oil them, they came right out of the box into the car.
I have no use for them. Stick with the regular filter, and I replace every 18 months or so.
I have a 2013 TL that I installed the K&N 33-2403 into today. Car has 18K miles and it's the first air filter replacement. I had a $10 coupon so I purchased it for $36.99 @ Walmart. Took a 10 mile drive and heard no audible change, also did not feel any difference in my pedal as I suspected I wouldn't. The reason for the change was the lifetime cost savings that I will realize not having to purchase another filter. I'll do a UOA in 6 months after my next oil change and report back.
Years ago I used one in my accord for years with no issue whatsoever. Hopeful to have the same experience and confident that will occur.
Years ago I used one in my accord for years with no issue whatsoever. Hopeful to have the same experience and confident that will occur.
http://www.nicoclub.com/archives/kn-vs-oem-filter.html
An actual comparison test.
Fairly stock, street driven vehicle, K&N is a waste of money.
An actual comparison test.
Fairly stock, street driven vehicle, K&N is a waste of money.
Filters are supposed to get more efficient as they get loaded up.
If you never clean your K&N will it eventually function as a normal filter?
If you never clean your K&N will it eventually function as a normal filter?
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(Note: The Purolator was reported to have a seal malfunction during the test and passed more dirt than it would have with a good seal.)
lol awesome. Even tears in the air filters.
(Note: The Purolator was reported to have a seal malfunction during the test and passed more dirt than it would have with a good seal.)
lol awesome. Even tears in the air filters.
K&N air filters: For the man who would rather buy bottles of cleaner and oil than replacement air filters.
I've had my K&N cleaner and oil for well over 10 years - how many filters would've I bought in that time ? That is also several filters, not just one to look after. As I've said several times - too much cleaning, too much oil.
Originally Posted By: Silk
I've had my K&N cleaner and oil for well over 10 years - how many filters would've I bought in that time ?
I'd wager no more than 3 if you had used a restriction gauge.
Plus you wouldn't need to touch the filter housing between changes, just glance at the gauge when you open the hood for other reasons.
I've had my K&N cleaner and oil for well over 10 years - how many filters would've I bought in that time ?
I'd wager no more than 3 if you had used a restriction gauge.
Plus you wouldn't need to touch the filter housing between changes, just glance at the gauge when you open the hood for other reasons.
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