Just HOW bad is K&N
 

Here's a link to a very well known BMW guru - kind of the Bruce Anderson of the BMW world.

http://www.seansa4page.com/resource/airfilter.html

(I've never used K&N on my porsches or other cars because to me, even if they let in 2% more dirt, its not worth it because there is no upside - i.e. no power increase).

I bought my K&N air filter when I first bought my car from Performance Products w/ dilusions of added HP, and superior filtering (This is before I knew Pelican Parts existed.) I guess it is really time to take the thing off and go with an OEM replacement. It ain't doing any good and there is pplenty of evidence that it is actually counter productive in protecting the motor from airborne particles.

Do you think that K&N and/or Performance Products would refund my money? After all it claims additional HP and extra protection for 1,000,000 miles. Obviously the filter can't live up to either of these claims.

Maybe they'll give you a cool collar in exchange for it!:D Jim

I like my K&N cone set-up. It may not make the car faster, but it sure frees up a lot of room to work around in the engine area. And if I never have to change the filter, eventually that savings will pay for the K&N.

Seems every automotive board has a similar thread about performance and invariably the K&N question gets asked. I liken this to threads about solid vs. drilled rotors in that it seems to come down to looks vs. performance.

K&N - I love that cone filter because it uncovers more of that p-car engine I love so much. Another bonus is that the filter is washable so no more buying replacements. Down side is the reported decrease in filtering quality and no measureable increase in performance.

Drilled vs. Solid rotors - love that 70's performance drilled look. No other measureable improvement but documented cases of failure in racing conditions and various heat/stress induced cracks. Think about it...not too many race cars have drilled rotors these days and instead go for surface area and mass to absorb/remove heat from the pads.

My choices, solid rotors and stock air filter and long engine life, put a K&N sticker on the box if you have to. Spend the money on beer.:p

David

I avoided this question in 101 Projects because I didn't want to bash any filter manufacturers in print. However, I do say to make sure that the filter you use meets or exceed's Porsche's original specifications for your car.

K&N filters do not. As such, I do not recommend them (even though I sell them - some people just gotta have them)...

-Wayne

K&N - for Kooks & Nuts

Yep, the power of junk science combined with heavy and clever marketing is incredibly strong . . .

Its really the way to make big money in America.

Actually, it appears as though the way to make big money is just to *say* you made big money. It evidently worked (for awhile) for Enron, Worldcom, and now Xerox.

Go corporate!

Okay! So what is a good K&N type filter?

I'm considering 6 of them Pipercross foam sock filters which fit over the standard ram tubes.

Cheers

You can turn blue in the face trying to enlighten people about certain things. If one value its 'look" more than it's function, go ahead and use it. If it saves room in the engine compartment (how much more room does a foam filter take over a K&N?), go ahead and use it. If you can clean it again and again, thus saving replacement costs, knowing it doesn't filter quite as good, go ahead and use it. Ultimately, one chooses to use what they wish despite the information on this forum from reputable sources. All you have to do is that information ... wisely.

Has anyone seen the late night infomercials on the Tornado (creates a vortex air flow)? I bet they've sold a bunch.

Sherwood Lee
http://members.rennlist.org/911pcars

Anybody tried cross-drilling or slotting the K&N filters for better flow? ;) I've been using cross drilled brake lines for years, and have had no brake overheating problems! :p

I used K&N on my Boxster and had no complaints until it came time to re-oil. I got a little over-zealous, and ended up fouling the mass air flow sensor with oil.

The $270 to fix that would've bought lot of stock air filters.... D'oh!

-Boyo

i dont understand what this is all about

K&N lets 2% more dirt in?? is that all??

So Wayne, what do you recommend those of us with Webers do? Are there any paper filters that will work?

Uh, Slakjaw.... going from 99% to 98% effectiveness on an air filter would be a 100% increase in dirt going in. Still with me? :cool:

That was enough for me. Pulled K&N this afternoon and put the stock paper one back in. I feel better already. My fuel injection system has enough problems without more dirt. In So Cal, we probably don't need to worry as much--as there are no 'dirt roads' anywhere I can even think of. There's just no dirt period.
But at this point, there's no gain worth the risk.
I'll stick with paper.

I'm probably in the same boat as many - my car had a Weber conversion done by the PO and it had K&N watershields on it when I bought. I've got a pair of their "Prechargers" ordered - fancy marketing name for some fabric covers that serve as pre-filters and get the particle size down to 0.005 inch. -- Curt

http://forums.pelicanparts.com/uploa...chrgrGroup.jpg


BTW: The wrap for watershield-type filters is part number E-3671PK (black), PR (red), PY (yellow), PB (blue).

Why do the 996 GT3 Cup cars have K&N similar BMC airfilters????

Why don't they have an airbox with a paper filter like street cars do?

OK,
I really have had it with these wild claims on K&N.
I did a dyno test ! has anybody else got dyno numbers to back up what they say ? I do ! Some 911's DO get more horsepower.As for the more dirt in the airbox, I check mine every couple of months NO dirt, I clean my airbox with 303 and yes it has a minascule amount of what I'd have to call dust.SO, I have a K&N, most every Porsche owner I know runs with K&N,especially on their track cars and I have dyno numbers to show an increase
in my 83SC.I got 7 hp with K&N ! I have 175hp at the rear wheels
with 237,000 miles on an origional engine with a busrch exhaust and cat by-pass. Now I am willing to have my mind changed, show me dyno numbers for an 3.0 stock engine that shows a power loss with K&N and I'll dump mine, till then..... well, I'll keep my extra 7hp !

7 hp with the K&N??!! I can't see how. Will you post your print-outs?