K&N or paper filter. Which is better at filtering air?

[mattd1979]

I was wondering if anybody knows which filter is better at catching fine dirt particles? A reusable filter like K&N or a paper filter. I was just curious as I figured that if the K&N filter flows better and uses a screen mesh and oil for a filter medium then fine dirt particles may pass through it more easily then a paper filter which appears less porous.

[Jesda]

I'm assuming that you drive a 1990-1996 Q45.

Do a NICO search. You'll discover that the OEM filter is hardly restrictive and most importantly, protects the delicate and expensive air flow meter.

[mattd1979]

When we got the Q the previous owner had switched to a K&N filter. The 45 has around 196,000 miles at this time. We bought it back in the first part of November.

[GreenQ45a]

SO is K & N a bad idea?

I was gonna buy one tomorrow. (really I was)

Mine is dirty as hell.

[CrimsonQ]

K&N equals oil...........imo thats bad with any car that has a very sensetive MAF right behind it. The oil will buildup on the sensor and you will have to clean it constantly. I had the same experience with my mustang and would never do it again.The only benefit I ever recieved from a K&N filter was increased sound from intake air, thats about it.Use that $45 and get some silverstars or something useful

[Jeff Williams]

The original filter does a great job filtering out the dirt. That is what it is designed for.

The K&N filter has an active filtering system, that uses oil to actively attract the dirt, while having a less dense filter media.

What that means, is that the factoy filter is fine, but must be changed more frequently, as it loads up, it becomes much more restrictive.

As the K&N loads up, it turns black, bit the pressure drop across the filter changes very little.

The oil does cause problems with the MAF only if you don't follow the directions, when you re-charge it. A lot of people clean it, spray the oil, then put it on the car (I used to). I would end up having to clean my MAF about every 2 to 3 months. Then, I went to a 2-filter system where I would clean and oil the first filter, and let is sit for a year while I used the second one, then swap it out and clean the other one. I keep my spare in the original box and plastic bag.

For the last 2 years, I have not had to clean the MAF.

If I were you, buy 2 or just buy 3 from Wal-Mart, and chan ge them every 4 months.

[Q45tech]

IF you measure the restriction of AN OEM paper drop in filter vs KN drop in vs no filter at all [even with 20,000 miles] on each filter you will find less than 1/2% [closer to 1/4%] restriction for filters at worst case 6900 rpm WOT.

95% of driving is idle to 2500 rpm........a range at which no filter has any measureable restriction.......the air flow is so tiny for a 274 cubic inch engine operating at 15% volumetric efficiency------making 10-25 HP.

By 200k the ring wear is significant [from cranking a cold engine-----cold oil doesn't lubricate well at all till it gets above 130F]. Way too late to make any significant changes or improvements.

Just change the Vavoline Extended Life 10w-40 oil/filter every 90 days 4,000 miles and the OEM air filter every year!

[maxnix]

Do a NICO search. You'll discover that the OEM filter is hardly restrictive and most importantly, protects the delicate and expensive air flow meter.

Very wise advice to heed.

Just change.........the OEM air filter every year!

And for the FY33, Y34, F50 and Y50 owners, change the interior cabin filter at the same time.