K & N air filter

Hi,

I thought I would comment on this. Yes, it is a very polarised subject. I believe that polarisation is due to misinformation and poor maintenance procedures.

1.Some performance air filters may let more particulates through, others will perform as good as a good quality stock paper element filter. Some stock paper filters are not too good either.
2. The MAF will probably get dirty after a period of time whether you have a K&N filter or a paper filter. I will say that if you over-oil your K&N then this may cause the MAF to require cleaning sooner however according to K&N they have tested for this and the test showed it does not happen. If your MAF is dirty or coated with something check your filter and air box etc for leaks.
3. A K&N filter requires periodic servicing, which is low in cost but requires some time. A paper filter requires periodic replacement which is fast but high in cost and not environmentally friendly. This is the reason dealers do not like serviceable air filters, because they require time to service them. This is good if you are a home mechanic (arent all rangie owners? )
4. The K&N filter will allow more air flow and filter as well due to better design. I will say that there are conflicting test reports on the filtering efficiency. Who do you believe? well that is the question of this topic. More air flow is probably not noticeable on stock unmodified rangies. Personally I did notice a very slight seat of the pants improvement and a very slight mileage improvement but in defence of my stock filter I would say it was a bit clogged (it didnt look bad though) (Dealer was supposed to replace it! hmmm) I believe that a properly maintained K&N will provide the same engine protection as a paper filter.
5. What is vitally important with both types of filters is that they seal correctly when installed. That needs to be checked and done carefully.
6. A K&N filter is a lot more expensive so it will take quite some time to realise any cash benefit when you buy a K&N. I figure about 4 stock filter changes which is equivalent to the cost of the K&N. (calculated on the filter cost from my dealer and what I paid for my K&N) Stock filter replacement interval is 24,000 miles (40,000 Km), that's 160,000 Kms before you are even.

My personal view is that the paper filter is too expensive so I fitted a K&N. I will be doing the services anyway. If you are having a dealer or mechanic do the work then probably stay with the paper filter, just makes sure that they, A: use a good quality make and B: they actually change it, not just "examine" it.

Oh, and Mark, how did you get a "2001 GEMS" rangie? The "bosch" had them by 2001 and lucas was in the past.

Cheers
Mick

Hi

Hmmm? This is all very interesting. I have been involved in discussions on K&N filters before. See the "debate" here http://www.rangerovers.net/forum/viewtopic.php?f=3&t=6921&start=15#p49516

I am a proponent of the K&N air filter. I installed the first K&N filter on the '89 Classic I had. There was a very noticeable improvement in overall running and performance. When I updated to the '94 Classic I replaced the standard filter with a proper K&N replacement that fitted in the standard RR air cleaner housing.

Here is the result of a dyno test with standard filter and K&N filter.

[attachment=0:hyr803io]RRDynoChart.gif[/attachment:hyr803io]

You will see that there is approximately a 5hp increase overall (107hp to 112hp) and that the power is improved throughout the rpm band. You will also note that the higher power is maintained for a slightly longer rpm range than the standard air filter, which shows the hp drops sooner. ie ~112hp between 4200rpm - 5200rpm (K&N) and ~ 105hp between 4200rpm - 4700rpm.

Further to this I NEVER had a maf problem with either RR, yet my current 2000 P38 has just had the maf replaced even though it has (probably) never been off-road and has always had it's paper filter replaced regularly (by Barbagallos (shudder)).

I believe K&N filters are at least as safe as the paper filters, do NOT damage the maf and certainly improve the running of the engine and improve power and economy. If the K&N filter is used and maintained PROPERLY according to the K&N instructions then there will not be any K&N induced maf problems.

It is a polarizing topic, always has been. Anyway, I actually know of someone who's K&N filter came over-oiled from the factory and damaged his MAF past the point of just cleaning it. It does happen, and if you over-oil at all by accident it absolutely can happen.

Aside from the MAF, the facts are that the stock paper filter has significantly more surface area for filtration than a drop in "performance" panel filter and WILL filter better, period. We're talking about trucks that do 60 MPH in NINE seconds, guys. I'll take better filtration, ESPECIALLY on something that goes offroad occasionally, than doing 0-60 in 9.5 seconds instead of 9.6. On my XJR or Bimmers I have always ran performance cone filters (Apexi Power Intake or AEM DryFlow) which I custom built to be true cold air intakes drawing air from down low. But, those cars never saw/see dirt or poor road conditions. And I would never run an oiled filter....forget that.

Just stick with OEM quality paper filters or go all the way on a performance vehicle, but keep it on the road then.