K&N Filter!
Printed From: Bavarian-Board.co.uk - BMW Owners Discussion Forum
Category: Technical & Model Specific Forums
Forum Name: General Motors
Forum Discription: This forum will deal with technical issues for the cars not dealt with in the other forums. These don't need to be BMWs!
URL: http://www.bavarian-board.co.uk/forum_posts.asp?TID=2550
Printed Date: 28-June-2024 at 22:17
Topic: K&N Filter!
Posted By: j_p_buckley
Subject: K&N Filter!
Date Posted: 08-July-2003 at 13:02
|
Hi, When I bought my Bmw (E36) 325, it already had a K&N airfilter installed... I was having a look at the filter the other day, and its got quite dirty... whats the best thing to do, replace it or clean it?! Are they easy to change over... I know nothing! :) Cheers ------------- Cheers, Jon http://www.paperclick.co.uk/jon/bmw325.jpg |
Replies:
Posted By: kbannon
Date Posted: 08-July-2003 at 13:42
|
just clean it http://www.knfilters.com/clningins.htm">http://www.knfilters.com/clningins.htm ------------- Current: 2009 E60 520d "Sport" tractor Previous: 1989 E30 320i SE 1997 E39 523i 2003 E39 525i Sport Individual |
Posted By: PhilC
Date Posted: 14-July-2003 at 22:27
|
Do K&N Filters even work??
Here's a link containing the opinion of a couple of 'experts' who think they are useless. http://membres.lycos.fr/technice31/mods.php Appreciate if you have any links to independent tests to prove otherwise. Thanks PhilC |
Posted By: kbannon
Date Posted: 14-July-2003 at 23:30
------------- Current: 2009 E60 520d "Sport" tractor Previous: 1989 E30 320i SE 1997 E39 523i 2003 E39 525i Sport Individual |
PhilC wrote:Posted By: PhilC
Date Posted: 15-July-2003 at 00:37
Guess so!!!!!
|
Posted By: j_p_buckley
Date Posted: 15-July-2003 at 10:34
| Even if they don't add any performance to the car, I just love the sound! :) |
Posted By: PhilC
Date Posted: 17-July-2003 at 11:43
Now your talking!!
|
Posted By: micky_h
Date Posted: 18-July-2003 at 09:15
| I think it depends on the apllication,how restrictive the intake is and location in regards to the rad.Some cars i've tried them on made no difference or lost power/torque (540,mk2 golf gti 8v),others I've seen increases in power (Civic 1.6Vti)and more torque produced lower down (306 Gti6).They are probably more effective if used in conjunction with a chip or freer flowing exhaust. |
Posted By: Guests
Date Posted: 20-July-2003 at 10:55
|
K+N are superb for carb applications but if you have one on an e30 or e36 throw it away or sell to someone.
These are cack on the e30 and e36 and thats a fact. |
Posted By: dlg_e30
Date Posted: 21-July-2003 at 10:19
|
Are we talking about replacement elements or induction kits here?
Truth is they do work, this is the reason racing teams use free flow filters instead of the paper items found in the cars original airbox!! I work for a company called Ramair and we produce replacement elements and cone filter type induction kits, the are some applications such as the Honda Civic type R and the Vectra 2.5V6 which yeild 10 bhp power increases (dyno proven each time). These filters flow more air than paper and as a result let the engine breathe easier, some engines gain power and some better utilise the power they have, K&N are widely regarded as the best for power gains, however they tend not to filter as well as some of the foam type filters (although they would claim they do of course). The kits are dependant on getting cold air from the front of the car to work properly which is why ducting must be set up correctly. The one i have fitted to my 320 E30 (Ramair) is certainly not cack, the car is slightly better on fuel when driving carefully, feels more responsive lower down all round and pulls noticeably better at the top end, quite noticeably in fact!. The noise is pleasant extra but is certainly not intrusive in any way, if anything adds to that straight six yowl. I would imagine in conjunction with a chip and free flow exhaust the filter would help enourmously, however even on its own a well designed kit will help your car breathe better, think about it a car runs on air and fuel..... |
Posted By: Guests
Date Posted: 21-July-2003 at 17:49
|
I am refering to the K+N only and not ramair or pipercross etc etc.
The K+N is renowned to lose power on the e30 engine throughout the rev range. I have a pipercross on mine and it is amazing, i have also tried green cotton and ramair and both were fantastic but the K+N was cack. |
Posted By: paul325i
Date Posted: 29-July-2003 at 01:21
|
I have to agree the K&N is not good in the nicest possible way. I'd also agree that they are good on carbed cars. The K&N is good if you use the replacement air filter and keep your standard air box (maybe with a few holes drilled into it) but the 57i induction kit for the E30 is crap, sapps torque from the low end and gives a small amount of improvement at the top end. The only real improvement that i noticed was that my top speed increased 5mph. But the same can be said for exhausts that make your car breathe better, a car with a full stainless high flow performance system loses alot of bottom end torque, which is fine if you are prepared to sound stupid by revving the t*ts of your car just to get it going, but if you refit a standard quality system say a genuine BMW, or Ernst then the car is transformed into a much easier to drive one. I was very much into the loud exhaust and the induction noise but performance wise your better off with a drilled box and replacement filter, an uprated manifold (intake and exhaust) and a very high quality 'standard' exhaust system. ------------- 
Visit http://www.geocities.com/paulav325i/ - My BMW Got an E30? Visit http://www.e30zone.co.uk - The E30 Zone |
Posted By: b318isp
Date Posted: 30-July-2003 at 13:21
| Don't be fooled by the cool air / shielding arguements too. Once the car is moving, air temperatures equalise in the engine bay. I know of two people who have verified this on the E30. |
Posted By: kbannon
Date Posted: 30-July-2003 at 16:10
go on Brendan - say it again!  ------------- Current: 2009 E60 520d "Sport" tractor Previous: 1989 E30 320i SE 1997 E39 523i 2003 E39 525i Sport Individual |
Posted By: kdevitt
Date Posted: 30-July-2003 at 16:49
| Have a K&N panel filter and stainless steel cat back exhaust on an E36 320i and have dyno proven gains of almost 10BHP, even if the filter only yields 2-3BHP its well worth it for the £30 that the filter costs! |
Posted By: paul325i
Date Posted: 31-July-2003 at 00:57
|
Your right about the cool air under the bonnet on lesser cars it is probably not designed as well so the temerature will stay higher all the time. The only time a K&N will not get the cold air it needs to make any improvement is if your traveling at normal in town road speeds of 20-30mph. The induction kit will actually be losing you power at low speeds, as its feeding the engine warm air direct from under the engine bay. With a standard manufacturers airbox the intention was to get a constant feed of air from outside the bay thus giving you your cool air = a few measly horses. -------------
Visit http://www.geocities.com/paulav325i/ - My BMW Got an E30? Visit http://www.e30zone.co.uk - The E30 Zone |
Posted By: b318isp
Date Posted: 31-July-2003 at 10:39
|
But you don't need much power at 20-30mph or in traffic.
I agree about the standard airbox - my E30 intake ducting is quite straight and feeds from behind the headlights. |
Posted By: lancelotII
Date Posted: 11-August-2003 at 13:14
|
You can't make any comparison between a race engine and a road car. The additional wear of the engine by flowing more air and therefore more dust and crap should be taken into consideration. Race teams use them because coupled with all the other factors getting more air into the engine makes power, so does running the engine up to speeds of 10,000rpm for a decent 4 pot, but you are not going to do this for a road car.
You could see 10bhp on a dyno just by doing the runs on different days or by using different tyres. Personally, I think if BMW thought they could release cheap horsepower with a rinky dinky air filter and a "wahoo" exhaust they would have done it at the factory. Why spend thousands od Euro's on engine design when you could just bolt 10bhp straight on........Think about it....... |
Posted By: dlg_e30
Date Posted: 15-August-2003 at 12:56
| NO BMW LEAVE IT TO COMPANYS LIKE HARTGE ETC..... |
Posted By: PikeyM3
Date Posted: 16-August-2003 at 16:44
|
You should also consider cost in this argument. It probably cost BMW pennies to buy or produce paper filters in a plastic filter housing. Add to that the fact that the get dirty and need replacing and you have your answer. BMW would not waste money on producing expensive woven cotton filters and directing air thorugh complex ducting for the sake of 10 bhp. Plus you only need to clean a cotton filter, you have to BUY a new paper filter! Pikey ------------- Old enough to know better, too young to care! |
Posted By: lancelotII
Date Posted: 20-August-2003 at 11:44
| You mean like the Alpina one on a B10. They turned the aircollector upside down, changed the element for an Alpina one which was the same as the BMW one except it had a different surround to make it fit the new air collector.............Filter element was exactly the same...... |