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MG MGA - K&N Filters

Will someone let me know the product number for the K&N Filters to suit the standard MGA air filter containers.....The market here in NZ is smll and the importers carry a limited range....Thanks Rex
Rex Thompson

Rex, Just got new K&N's -- haven't fitted them yet.
E - 3180
Barry
Barry Gannon

Barney's site gives all the details.
http://www.mgaguru.com/mgtech/carbs/cb201.htm
Mike Ellsmore

Without wishing to hijack the thread, once you fit the new filters, is it straight forward to make the mixture richer in the normal way. I say richer, but what I really mean is the new filters will improve air flow so that more fuel will be needed. I seem to remember hearing somewhere that there can sometimes be a problem increasing the fuel content sufficiently. Is that correct?
Graham M V

Thanks guys...Barney's site gives it all....Rex
Rex Thompson

If the filter is clogged you have a problem. Otherwise most any air filter will work well enough for air flow, and none will restrict flow enough to make any significant difference in fuel mixture. If proper fuel mixture is beyond the range of the adjusting nut, there is something else wrong with the carb.
Barney Gaylord

Graham
No problem with my K &Ns -fitted easily and No adjstment required for the mixture-Did have to drill out the backplate to fit the rocker Breather hose. When I fitted them to my MGB some years ago Oselli did say I might require a slightly leaner needle as the air flow was better- I never bothered as that was fine also
Paul
P D Camp

Rex
I fitted new K&N filters a few weeks ago.
No. is E-3212
They fit perfectly without needing to alter the original Vokes housings. I fitted them with new felt rings (2 each) and the stub stacks. This set up works very well.
André
André M Kunz

They may fit, but they don't filter. The reason that you get more air flow is that the filters do not stop anything smaller than a boulder. A friend put these on a flow bench with the standardized dust particles used for filter testing, and found that the K&Ns did a very poor job of stoping the dirt, where a standard paper filter did a much better job. I will gladly give up a little air flow for a filter that stops the dirt and saves my enging.
JP Jim

JP, You say -- "A friend put these on a flow bench with" ---- That is very anecdotal!
Your post suggests your friend has the equipment and knew what he was up to.
I would like to see the results.
Can you show us the money? Let us see these claims backed up with hard evidence!
Barry.
Barry Gannon

there are excellent comprehensive test result charts in Vizards book which show the superior air and dirt removal performace of K&N filters compared to other types/makes....I believe them....
Neil Ferguson

Neil,
Do you have Vizard's book? If you do, could you scan the test results and present them on this forum. I am sure a lot of members would be very interested in seeing the results.

George
George Raham [TD4224]

will do..but away from my car and books..will do on Thurs ..
It is a wonderful book...
Neil Ferguson

George..an IPhone pic of the relevant page along with the commentary. It seems to me these results ....in very reliable book .....plus experience by a multitude of users incl myself is fairly conclusive...K & N are good filters ( incl. removal of boulders..even small ones!) and superior in clean and dirty condition to paper units. I would add that Vizard says he selected the best performing paper element for this comparison..some were much much worse and he has another chart showing this.. Sorry about the angle....


Neil Ferguson

Niel, that is just pressure drop / airflow data. The co
ncern was that they let through fine dust.Is there any data on capture ratios?
Art Pearse

There are also well documented tests published on the net, from AC Delco testing facilities, showing what a really good paper filter can do. And backyard tests showing dirty intake pipes downstream of K&N filters. Sorry I can't find the links, but I found them more than once - you should be able.

I've been promoting Vizard since his very first book came out c 1977, and still consider his stuff to be one if the best and most useful reference sources.

My overall take is that good clean paper filters are clearly superior overall, but suffer severe flow restriction past some fairly early point on the route to "dirty"; not an issue on a well designed road car but very much in not so good designs or an off road racer.

Mazda has a self cleaning sort of labyrinth that gets all the big wet stuff out before the air gets to the flat panel paper filter. When it does, the dirty side is the bottom, so the thing is self cleaning as you hit bumps and vibrate your way down the road - remarkable, last forever - clean! Even the bottom of the filter box has deep grooves to catch fallen dirt, keeping the dirt from being sucked back into the airstream; hard to clean but not very often - my Mazdas with 150,000 miles have less crap in the filter box than I have sometimes found in a set of MGB air filters after 12,000 mi.

Serious dirt with serious high flow requirements call for different characteristics - you sacrifice some fine filtration when new for a lot of flow of acceptably clean air mid race (or hot laps on a dirt track!) on. And the K&N actually filters better dirty. Since these were developed for life critical desert military service, there is no doubt that they are effective under those conditions. This may tell you a lot more about what filtration is necessary for high performance engine life than does advertising and internet musings.

A major point with K&N is that they can be fairly small, a definite advantage in tight spaces, and even made to order.

FRM
FR Millmore

Fletcher.....a great overall review of the practicalities and compromises involved in filtering....and trying to satisfy two contradictory objectives...
...loads of air
...dirt removal.
Art...Vizards 3rd edition "tuning A series etc..' does not have an objective experiment measuring the efficiency of air born crap removal by particle size etc... but does have some strong directional comments on the subject based on his desert racing experiences with different filter mediums....I attach a note from the book on the K & N units .


Neil Ferguson

Neil, not enough res for my eyes!
Art Pearse

Yep, don't know where the error is, but I have choice of a large postage stamp or a small one!

FRM
FR Millmore

Sorry about the eye straining IPhone pic....My scanner is o/s . Try again below....Vizards comment is a qualitative judgement based on his experience...


Neil Ferguson

Not what I would call good evidence of dust retention ability.
Art Pearse

Art..I have to say that for me the fact that the filter can take out the sort of desert bull dust we also often get in these climes and cake it to 3/16in gave me major comfort. This is in combination with a load of onsite comments on filters on this site and many other sites. Vizard also discussed experiences with various paper units...some quite good and some crap .. but they clogged up quickly in heavy duty. I always judge such qualitative experience on the basis of the quality of the person making them and Vizard fits my top requirement re the latter.
If you come across a set of curves showing particle size, superficial velocity, weight,time etc etc for various types please advise...
K & N info on tests below..but beware as it is paid for by the supplier ....so cigarette lobby rules apply!!

http://www.knfilters.com/filter_facts.htm
Neil Ferguson

This thread was discussed between 19/06/2012 and 07/07/2012

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