6 year old study of air filters, including the venerable K&N!

[StageLeft]

I had not seen this before. I'm sure some of you have. Basically backs up what most people say anyway, which is "don't believe the hype".

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=11674

 

[Eli]

Wanting excellent filtration and good airflow is like wanting power and economy. It just isn't going to happen. lol

 

[Harrod]

Isn't this study linked in someones signature on this forum? Something about 45 times more dirt into your engine.

 

[Throckmorton]

Yes, my sig. The link in my sig has bar charts too

 

[amdhunter]

Isn't this study linked in someones signature on this forum? Something about 45 times more dirt into your engine.

Dumb question time.

Will it be so much more dirt getting into the car, that the engine will seize up or something?

Should dirt in an engine really be that much of a concern?

 

[Howard]

Dumb question time.

Will it be so much more dirt getting into the car, that the engine will seize up or something?

Should dirt in an engine really be that much of a concern?

It can accelerate the wear of various parts inside the engine. With modern engines, small amounts of dirt shouldn't do much IMO.

<-still a proponent of OEM filters

 

[StageLeft]

Yes, my sig. The link in my sig has bar charts too

Just saw it in the wealth dist thread. Reading it now

 

[fbrdphreak]

I finally removed the K&N intake that the previous owner had installed on my car. Not only will I get the money from selling it, but I get rid of the obnoxious WHOOOOOOOOOOSHHHHHH every time I build any boost. And better dirt filtering to boot, woot!

 

[Bignate603]

It can accelerate the wear of various parts inside the engine. With modern engines, small amounts of dirt shouldn't do much IMO.

<-still a proponent of OEM filters

They tend to be cheap and have good filtration, they're hard to beat.

 

[skyking]

I've exceeded the capacity of my OEM so I will have to move to a BHAF(Big Honking Air Filter) on my Dodge diesel. before I did the larger mods it was more than adequate.

 

[thescreensavers]

I have the Wix/Napa gold filter

 

[Bignate603]

I've exceeded the capacity of my OEM so I will have to move to a BHAF(Big Honking Air Filter) on my Dodge diesel. before I did the larger mods it was more than adequate.

Did you just move to a significantly larger OEM style filter and airbox?

 

[skyking]

No, I have not purchased it yet. Essentially it is a tractor or heavy equipment filter.
http://www.fleetfilter.com/filter/42790.html
That will clamp right to my turbo inlet hose.

 

[Vette73]

Dumb question time.

Will it be so much more dirt getting into the car, that the engine will seize up or something?

Should dirt in an engine really be that much of a concern?

Not only will it increase wear on the car it can hurt power over the long haul. It can also cause your Mass Airflow Sensor to get clogged up and not read right.

The last owner of my Corvette said he replaced the air filter. I did not see a sticker on it so incorrectly assumed it was a paper filter. I noticed that on very hot days or if I got on it hard it would spark knock. I went over the car and could not find anything that would cause it. It was still under warranty so I took it to 2 dealers and they could to find anything but agreed the spark knock was not normal. One said drive till the engine light came on or something broke. I was not happy with that so I went to do a oil change and removed the air filter to dust it off. That’s when I saw the K&N. I removed the MAF sensor and cleaned it with some q-tips, don’t do this unless you have exp at it, and it fixed the spark knock 100%.
Once I cleaned the MAF sensor and put in a paper filter I have not had any issues with my Corvette since.

If you have modded your car/truck so much it REALLY needs more air; get a bigger paper filter and intake tubing.

 

[StageLeft]

Not only will it increase wear on the car it can hurt power over the long haul. It can also cause your Mass Airflow Sensor to get clogged up and not read right.

The last owner of my Corvette said he replaced the air filter. I did not see a sticker on it so incorrectly assumed it was a paper filter. I noticed that on very hot days or if I got on it hard it would spark knock. I went over the car and could not find anything that would cause it. It was still under warranty so I took it to 2 dealers and they could to find anything but agreed the spark knock was not normal. One said drive till the engine light came on or something broke. I was not happy with that so I went to do a oil change and removed the air filter to dust it off. That’s when I saw the K&N. I removed the MAF sensor and cleaned it with some q-tips, don’t do this unless you have exp at it, and it fixed the spark knock 100%.
Once I cleaned the MAF sensor and put in a paper filter I have not had any issues with my Corvette since.

If you have modded your car/truck so much it REALLY needs more air; get a bigger paper filter and intake tubing.

That is harsh. I wonder why people still buy K&N.

 

[darkswordsman17]

That is harsh. I wonder why people still buy K&N.

Marketing.

We've even had one or two people from K&N actually post on here. They've done it other places as well, and I believe its gotten pretty ugly in some cases (as in lawsuits threatened).

 

[Bignate603]

Marketing.

We've even had one or two people from K&N actually post on here. They've done it other places as well, and I believe its gotten pretty ugly in some cases (as in lawsuits threatened).

I remember that, it absolutely backfired. I can't believe they thought that was a good idea.

 

[halik]

I have hard time believing that you will see no power increase when you remove air restriction. K&N cannot filter less, yet let in less air. The two are mutually exclusive.

Also the internet is full of dyno sheets with before/after K&N, realistically you pick up couple hp at most.

 

[thescreensavers]

That is harsh. I wonder why people still buy K&N.

Just becuase to say they got K&N, they dont really know it filters worse they think it filters better, you also need to keep oiling it which many dont do...

I have hard time believing that you will see no power increase when you remove air restriction. K&N cannot filter less, yet let in less air. The two are mutually exclusive.

Also the internet is full of dyno sheets with before/after K&N, realistically you pick up couple hp at most.

On many cars you simply wont see anything. IE my car.

 

[halik]

Just becuase to say they got K&N, they dont really know it filters worse they think it filters better, you also need to keep oiling it which many dont do...




On many cars you simply wont see anything. IE my car.

What do you drive? Generally FI cars and highly efficient/big motors will benefits the most - it's a function of how much air you're sucking in. Something like like a honda civic probably won't see anything at all.

On the other issue - I think these things come over-oiled from the factory. Every single I've ever bought I had to dab with a bunch of paper towels before installing.

The one on my 2.7T went 30K w/o an issue.

 

[Vette73]

I have hard time believing that you will see no power increase when you remove air restriction. K&N cannot filter less, yet let in less air. The two are mutually exclusive.

Also the internet is full of dyno sheets with before/after K&N, realistically you pick up couple hp at most.

Most cars are not limited by the air filter. Kinda like adding a larger water pipe to your house should let more water in. But if your shower only needs what the smaller line can supply you would not notice a differance. Now if you "modded" your house (extra shower or larger head) then yea extra water would help.
But most do not mod their car enough to warrant it. Even if they do there are other options that work and do not let in extra dirt. Such as a larger paper filter and better tubing to the intake.

Also a couple horsepower is well within the margin of error for a dyno.

 

[halik]

Most cars are not limited by the air filter. Kinda like adding a larger water pipe to your house should let more water in. But if your shower only needs what the smaller line can supply you would not notice a differance. Now if you "modded" your house (extra shower or larger head) then yea extra water would help.
But most do not mod their car enough to warrant it. Even if they do there are other options that work and do not let in extra dirt. Such as a larger paper filter and better tubing to the intake.

Also a couple horsepower is well within the margin of error for a dyno.

Multiple runs, standard error decreases with the square root of n

 

[Vette73]

Multiple runs, standard error decreases with the square root of n

Got a link to see?

 

[halik]

Got a link to see?

Not off hand, but put in 'K&N dyno filter' into google and you'll get a boatload of sheets showing marginal gains with the filter. Unless your argument is* that all dynos have a bias to show better numbers with K&N, independent observations can be used the same way as multiple runs.


(*i suppose or that internet only shows dyno sheets where K&N increases output)

 

[Vette73]

Not off hand, but put in 'K&N dyno filter' into google and you'll get a boatload of sheets showing marginal gains with the filter. Unless your argument is* that all dynos have a bias to show better numbers with K&N, independent observations can be used the same way as multiple runs.


(*i suppose or that internet only shows dyno sheets where K&N increases output)

Only ones I have seen are single pulls. Even then they show maybe a couple HP and even then its at the very peak and torque shows little to no diff. as well.

Heres one...

http://forums.tdiclub.com/showthread.php?p=2987755

The K&N pulled .07 more HP. Well within the margin for a dyno.