Thread: The K & N air filter

Except when the K&N is flowing it's best it allows debris into the engine until it "clogs" which is when it starts to filter more particulates.. at that point it's now flowing less than the Paper filter - even when it's partly dirty..

Silicates etc all pass through the K&N into the engine, into the oil etc and increase wear..

What a K&N does do, is add a bit of induction noise for those Boy Racers to smile about..

Now with the paper filters - filters aren't filters - make sure the number of pleats and surface area are as per OEM or better...

Originally Posted by sierrafery

From some tests i've seen the pressure drop was measured after the filter by using a blower in front of it which is not the same with a pressure drop based on suction IMO.... anyway as i said i made my own test with nanocom on live data and there was up to 4 units AAP drop with paper filter while only max 1 with K&N so that's for the Td5.

There is only one test you need for a K&N filter and that is take it out hold it up to the sun and if you can see pin ****** of light, then paint it green and throw it in to tall grass.
Have just completed installing a GM 6.2L V8 into a GU patrol replacing the ZD30 that was totally ruined by dust getting into the engine through a K&N Filter. No compression at all, inlet ports caked with dust, all this in only 3 months of offroading.
My BA GT was fitted with a cold air setup and a K&N filter (still got the detergent and oil) and after 5K bore was glazing and rings not sealing, luckily for me the local Ford dealer mechanic said to dump the K&N **** and go back to OEM paper, at 15K engine was replaced under warranty.
If you believe a K&N filter has a place on a road car or 4WD then go ahead, more business for us Mechanics, Regards Frank.

I thought we are speaking about Td5's here not 6l V8s... my engine is nice and clean after 150K km only with well serviced K&N and the compression is like new... each on his own though, i'm just sharing my own experience not trying to convince anybody.... if somebody can show me a scientific experiment where any particle from the size that can pass through any filter can ''survive'' the combustion i'll stand corrected and throw the K&N to the bin

Originally Posted by sierrafery

I thought we are speaking about Td5's here not 6l V8s... my engine is nice and clean after 150K km only with well serviced K&N and the compression is like new... each on his own though, i'm just sharing my own experience not trying to convince anybody.... if somebody can show me a scientific experiment where any particle from the size that can pass through any filter can ''survive'' the combustion i'll stand corrected and throw the K&N to the bin

You also don't have Bull Dust over there... that talc sized Silica is abrasive as hell..

Silica - melting point 1,414c well above combustion..

And you're forgetting the function of a 4 cycle engine..

1. Piston down, Fuel (at relevant point) & Air In with silica sticking to oiled bores...
2. Piston rises up and the rings & bores scrape against this matter...
3. Ignition and piston travels down
4. Piston up and exhausting combustion gasses..

See 1 & 2 for when the oil becomes contaminated, the bores and rings get damaged...

Now, what is it you were saying about particles?
They don't even need to suffer combustion to cause damage - AND - they don't suffer temperatures below 1,400c


And so endeth the lesson

P.s: And road dust, the sealed street type is composed or Carbon and Silica - the carbon from previous combustion process which won't suffer LOI...

Lesson learned ...though how much is the silica dust concentration down there cos if it's that bad to ruin an engine in few years after it was filetered even by an unefficient K&N i think that pulmonary diseases are the primary risk not the wear of an engine.. which AFAIK is not the case

Originally Posted by sierrafery

Lesson learned ...though how much is the silica dust concentration down there cos if it's that bad to ruin an engine in few years after it was filetered even by an unefficient K&N i think that pulmonary diseases are the primary risk not the wear of an engine.. which AFAIK is not the case

Road dust is obviously everywhere...

"Offroad dust" is generated by the vehicle(s) lifting it into the air....

You get more performance gain driving at a cooler time than by using a K&N..

Originally Posted by sierrafery

I thought we are speaking about Td5's here not 6l V8s... my engine is nice and clean after 150K km only with well serviced K&N and the compression is like new... each on his own though, i'm just sharing my own experience not trying to convince anybody.... if somebody can show me a scientific experiment where any particle from the size that can pass through any filter can ''survive'' the combustion i'll stand corrected and throw the K&N to the bin

Yeh, every Truck manufacturer in the world, show me ONE that uses a K&N oiled air filter, I'll see if I can find the Pics of the air inlet tract of my BA GT 5.4L.
What the hell has engine size got to do with it, when was the last time you had an oil analysis, you might be in for a shock, does your filter pass the "hold up to light test" it's just plain commonsense, if you can see through your filter, then it is NOT a filter