Outer Limits 4x4 Board

my next purshase will be made based on these results!
also leave any opinios why you like one over the other.
It will be for a 2H.
Cheers

i got a finer filter near ten years ago it's still going

I got a finer filter in my lux and wouldn't uyse a paper one again. Sure the foam costs more initially, but it's once off, and can be washed when dirty.

Hi all...All dirt motorcycles use a foam air filters.....All aftermarket turbo's recomend to don't use foam air filters.


peace...

I run a foam air filter with an after market turbo, why would it be a bad thing. I would have thought that a foam filter would be better with air flow and easier to see when it needs a clean

Something about foam particles as it perishes pitting the blades of the turbo...though could be wrong.

Muddy

phippsy wrote:I run a foam air filter with an after market turbo, why would it be a bad thing. I would have thought that a foam filter would be better with air flow and easier to see when it needs a clean

no matter how well you maintain a foam filter, they deteriorate over time and particles of foam (usually laden with chunks of dirt and grit) can be drawn into the engine. With an aftermarket turbo you can be drawing up to 200% the mass air flow through the filter, which means it (a) gets dirty twice as fast (b) has a bigger pressure drop across it. when foam filters get very dirty they clog very quickly, which increases the pressure difference across the filter. It can happen that a clogged foam filter, loaded with dirt and crap stuck to the sticky oil, will collapse and BIG chunks of filthy filter foam will go through the turbo compressor. then the chunks of filthy foam and shards of broken off compressor wheel blades go through your inlet valves, get crushed between the piston and the head on the compression stroke, then munched in the exhaust valve, before being ejected via the exhaust turbine of the turbo. in a fraction of a second your engine and turbo are an expensive pile of scrap metal.

Foam filters only flow better than paper elements when they are very clean, and unlike paper, which doesn't stick all the dirt to it, clog very quickly. after a few hundred km (less in dusty conditions) a paper filter will flow better than a foam element. To clean a foam filter, you need a solvent (usually turpentine) and a lot of it, and a bottle of sticky filter oil. A paper filter element can be knocked on something to get most of the dirt out, then blown out with compressed air, and in the case of toyota factory filters, washed in good old water (you need a lot of water true, but rivers and creeks are usually full of the stuff, I've never fouund a turps creek)

The cost benefit of a foam filter over paper (even using the 'expensive' factory ones) is negligible (or negative!) once you factor in the cost of maintenance of the foam filter (solvent, oil) and the airflow benefit is very small at best (probably less than 1% in most applications) and only applies when the filter is very very clean.

I wouldn't go so far as to say foam filters were a gimmick but if you want one to (a) save you money (b) increase the power of your engine (c) reduce complexity of service, you need to reconsider.

cheers

Brian

I have tried both types on different vehicles and they have good or bad points.

if you have heaps of time and remember to check the foam ones, they seem the go. but the oil and cleaning stuff is WAAAY overpriced.

paper ones seem a bit low tech and dodgy, but i have become a huge fan of simple changing them more often.

I am lucky on my 40, it has a dodgy air box and the old commodore carby air filters which are about 5 bucks a go fit there sweetly.

compared to 100 plus for a foam one and about 40 for the finer filter care pack.

and i found on my hsv that the finer filter got dry and full of crap really quickly. in a 4x4 it would be worse.
weigh up the $$$$.

dumbdunce wrote:

phippsy wrote:I run a foam air filter with an after market turbo, why would it be a bad thing. I would have thought that a foam filter would be better with air flow and easier to see when it needs a clean

no matter how well you maintain a foam filter, they deteriorate over time and particles of foam (usually laden with chunks of dirt and grit) can be drawn into the engine. With an aftermarket turbo you can be drawing up to 200% the mass air flow through the filter, which means it (a) gets dirty twice as fast (b) has a bigger pressure drop across it. when foam filters get very dirty they clog very quickly, which increases the pressure difference across the filter. It can happen that a clogged foam filter, loaded with dirt and crap stuck to the sticky oil, will collapse and BIG chunks of filthy filter foam will go through the turbo compressor. then the chunks of filthy foam and shards of broken off compressor wheel blades go through your inlet valves, get crushed between the piston and the head on the compression stroke, then munched in the exhaust valve, before being ejected via the exhaust turbine of the turbo. in a fraction of a second your engine and turbo are an expensive pile of scrap metal.

Foam filters only flow better than paper elements when they are very clean, and unlike paper, which doesn't stick all the dirt to it, clog very quickly. after a few hundred km (less in dusty conditions) a paper filter will flow better than a foam element. To clean a foam filter, you need a solvent (usually turpentine) and a lot of it, and a bottle of sticky filter oil. A paper filter element can be knocked on something to get most of the dirt out, then blown out with compressed air, and in the case of toyota factory filters, washed in good old water (you need a lot of water true, but rivers and creeks are usually full of the stuff, I've never fouund a turps creek)

The cost benefit of a foam filter over paper (even using the 'expensive' factory ones) is negligible (or negative!) once you factor in the cost of maintenance of the foam filter (solvent, oil) and the airflow benefit is very small at best (probably less than 1% in most applications) and only applies when the filter is very very clean.

I wouldn't go so far as to say foam filters were a gimmick but if you want one to (a) save you money (b) increase the power of your engine (c) reduce complexity of service, you need to reconsider.

cheers

Brian

Ill second that.

I will third that.

I ran a foam filter in a hilux with a snorkel and it was a complete PITA - twigs, leaves, and bugs sucked or pushed in through the snorkel would get stuck onto the filter making for a big wet oily muddy mess to clean up after every summer trip.

plus, manufacturers (toyota in particular) put quite a bit of effort into designing filter housings that spin the chunks away from the element, keeping the filter clean, and ussually have a small trap or canister to catch them. A foam filter ignores all of this as everything end up stuck to the stoopid thing.

I think they have a place in race cars though that rarely have the room or make too much power etc for a stock airbox and are serviced very frequently.

PS I am a bog fan a K&N filters though - they are not too sticky, don't lmake a blue runny mess of the airbox and seem much easier to clean.

I will also agree that it traps everything and is a pain. Still if you're dead keen to get one then the shops like Big W and k Mart sell filter oil cheaper than FF does. It has a motorcycle on the bottle. Living in a dusty environment it clogs real quick. Now my FF (from another vehicle) is sitting on a shelf filthy and gathering more dust.

Muddy

i sell and use unifilter (foam air cleaner)
i would recomend this product to everyone .
giving better air flow etc...
have u ever tryed to run water threw an oily rag ....
i had a hj45 with a 3.6 l h motor . with out a snorkel .
sucking water in the air intack . but neaver past water into the motor ...

Gwagensteve wrote: I am a big fan a K&N filters though - they are not too sticky, don't lmake a blue runny mess of the airbox and seem much easier to clean.

I think it has been shown in numerous filter comparos that surgical cotton filters like K&N flow plenty of air and don't clog like foam filters, however they way they achieve extra airflow is by (at the start when the filter is clean) letting too much grotty stuff past. They belong on the track where engines are rebuilt frequently and grotty air is not the primary cause of engine failure.

from K&N's own advertising propaganda:

The dirt particles collected on the surface of a K&N element have very little effect on air flow because there are no small holes to clog. Particles are stopped by crisscrossed cotton fibers and held in suspension by the oil. As the filter begins to collect debris, an additional form of filter action begins to take place because air must first pass through the dirt particles trapped on the surface. That means the filtration efficiency of a K&N element actually increase as the filter collects dirt. Tests have shown a K&N E-1500 filter will flow 60 percent of its maximum flow capacity after 50,000 miles of street use. And, considering a new K&N flows half again as much air as a comparable paper element, that same filter will provide all of the air the engine needs even after 50,000 miles.

what this says to me is that the filter starts out with a less than acceptable filtration efficiency (which they fail to define, but which probably means % of a certain particle size allowed to pass), relying on grit particles to flow close enough to the oily cotton to be trapped in the oil. Not acceptable in my book. I'd far rather my engine losing 2% of its potential peak power than losing 100,000km off its potential life. 2% more fuel over 300,000km (say between $500 and $1000 over 15 years) is a lot cheaper than an engine rebuild after ten years! It's meaningless to say that a filter flows 150% the air of a comparable paper element when in most cases the FACTORY paper element for most engines will easily flow 200%+ of the engine's requirements. Note also they make no mention of offroad use and "street" use is underfined. Street use in a city suburb is a lot different to street use in a dusty country town.

spend the extra filter $$ on slick 50 to put in your oil, it will liberate millions of horsepower

i asked a dts [dynamic turbo systems rep] about finer filters n etc on turbos his reply ;ever tried breathing threw a sponge while running around the block several times. also have seen dyno results of a car running both paper n finerfilters the paper gave a better result plus who wants to spend how long cleaning n preping a filter easyer to buy n replace . unless u run a genuine toyota filt wich is washable too ,hope info helps on the final decision