Outer Limits 4x4 Board

hey guys i got a 93 gq patrol 4.2 and a mate was telling me bout foam filters and how good they are and that there beta then k&n filters but i was wandering if they are really that good ? and wat are the benefits ?

There was a thread on here discussing all things filter related. Think it was based on Stock Vs K&n Vs Foam


*edit*
here it is

http://www.outerlimits4x4.com/viewtopic ... am+filters" onclick="window.open(this.href);return false;

Hi all...ALL Motocross,Enduro,Trials and Trail Motocycles use foam filters.These Motorcycles are designed for dirt use.It speaks volumes to me.

mickbeny wrote:Hi all...ALL Motocross,Enduro,Trials and Trail Motocycles use foam filters.These Motorcycles are designed for dirt use.It speaks volumes to me.

But do the engines last? Most motorsport engine would be unconcerned with longevity, and most ag bikes wouldnt do the sort of km that a 4WD tourer would be expected to do.

mickbeny wrote:Hi all...ALL Motocross,Enduro,Trials and Trail Motocycles use foam filters.These Motorcycles are designed for dirt use.It speaks volumes to me.

All that speaks volumes about are race motorbikes, where engine life is measured in hours, not thousands of hours.

Earthmovers, trucks, agricultural and military equipment use paper filters- speaks volumes to me.


Steve.

DAMKIA wrote:

mickbeny wrote:Hi all...ALL Motocross,Enduro,Trials and Trail Motocycles use foam filters.These Motorcycles are designed for dirt use.It speaks volumes to me.

But do the engines last? Most motorsport engine would be unconcerned with longevity, and most ag bikes wouldnt do the sort of km that a 4WD tourer would be expected to do.

Not to mention the race engines would have filters cleaned and oiled every few hours of use.

It's not hard to be better than a K$N. Paper filters are the best to actually filter, depending on what you're doing a pre-cleaner can be a big advantage in keeping the filters cleaner for longer.

hey that link did not really help me much sorry mate and so if i stick with paper filters is there any brand that i should get thats is beta ? or are they all the same ? cheers guys

gqmudder91 wrote:hey that link did not really help me much sorry mate and so if i stick with paper filters is there any brand that i should get thats is beta ? or are they all the same ? cheers guys

Genuine. Toyota genuine filters are washable (Nissan may be the same) and don't cost a whole lot more than list price for a ryco.

Hi all...Ive been involved in dirtbikes all my life.Foam filters are oiled of coarse.The inlet ducting leading to the carby gets lined with oil over time.One way to check if filter is working properly is to rub your finger on the inlet ducting and see what coulor the oil on your finger is,Never have i seen it other than the clean color of oil,If the ducting gets dirty over time you know you have some kind of filtering issue.
Ofcourse dirt motobike engines arfe high performace high reving engines,so naturally its extremely important that they have the best filtering characteristics along with high performance.The trade of is they clog quickly and need regular cleaning.

Road bikes are also high performance and high reving engines,They use the dry type filters like cars.

Dirt bikes do not have good filters. They use foam because it's the best they can fit in the space available. What's the maintenance interval on those filters? 5 hours?

[quote="KiwiBacon"]Dirt bikes do not have good filters. They use foam because it's the best they can fit in the space available. What's the maintenance interval on those filters? 5 hours?[/quote

Hi all...Thats rubbish.Do you know the costs to rebuild a modern 4 stroke dirt bike engine??????Put it this way,My 1HZ was cheaper for similar work.Dirtbikes have little engines up to around the 500cc mark.If anything i would say a dirtbike has a bigger filter per cc vs a 4wd.

Matainance intervals is to do with how long your in dust.A few years ago i was on one of my anual trips to the Cape,The bulldust was so bad i had to clean my airfilter daily 2 days in a row,Thank goodness i had a genuine Toyota cleanable filter.Dirtbike spend almost 100% eating dust[unless your always up front] unlike a 4wd.But when all is equal 4wd need regular cleaning too.

Mickbeny, I think you're wrong, and I think you've proved it in your post.

A Dirtbike has a large filter for what it is, but not a large filter based on the CFM the engine is consuming and the environment its operating in. A 1HZ has a well sized filter for general use, but in an extreme environment, you needed to clean the filter daily , indicating that a pre cleaner would have been VERY useful.

(Out of interest though, how did you know the filter needed cleaning? did it look dirty, or did the warning light come on? reason being, opening a filthy filter housing to service a filter puts lots of dust into the intake tract. Filter housings should be opened as little as possible for engine life. A dirty filter filters better than a clean one)

Have a look at the filter on a small excavator. That's going to be running about the same CFM as a large dirt bike, give or take, ( but they are running at that peak CFM continuously) and its filtration hasn't been specced on space, but on efficiency. They typically run a 4 or 6" cyclopac type filter and a pre cleaner. In that application, the precleaner might get emptied daily, or when it's full, but the filter might only need a change very few hundred hours. There's no room for a filter that good on a bike, but there's no point, because who cares if your filter is still pristine but the motor is getting a rebuild anyway?

I'd rather have a larger filter that needs infrequent service, filters the air very effectively, and provides a performance increase through increased filtration area rather than a less effective filter with less surface area to provide a performance increase at the expense of engine life.

Engine manufacturers I have spoken to / worked with think that anything under about a 5L diesel is a throwaway engine.

"Off highway" heavy vehicle (e.g. excavator) engines are expected to last about 10000x longer than a dirt bike engine (in terms of hours between rebuilds). As a result they have much better filters.

The proof that you can get away with crap filters on a dirt bike is here:
http://www.scottsperformance.com/produc ... PartType=3" onclick="window.open(this.href);return false;

Filters are not sieves. Filters perform MUCH BETTER than any sieve that can flow the same amount of oil (i.e. the same pressure drop for a given flow rate) - So replacing your 4-stroke oil filter with a stainless sieve would mean your filtration performance is many times worse. However... there are lots of people out there running them.

Hi all...Foam filters cake up to a point they can get completely blocked.For cars,4wd,industrial machinery ect it would mean way to much maintenance,To the point it wouldnt get done.Oiled foam filters arent really a practical option in the real world.
Dirtbikes however get riden on weekends,If your pedantic you would clean your filter after every ride.If not,A quick inspection,if it doesnt look that dirty clean after a few more rides,the environment dictates cleaning.

As for my landcruiser filter needing cleaning,The warning lites never came on but i did notice the vehicle seemed a little sluggish with a little more black smoke than useual.On the Cruiser utes the inlet sucks from the top of the filter housing,Which is actually the lid of the filterr.It is next to impossible to get dirt into the ducting.On a side note,This particular trip i had fine bulldust sucking into my filter via the thread where the wingnut holds the filter lid down,I fixed this with some grease on the thread.

mickbeny wrote:Hi all...Foam filters cake up to a point they can get completely blocked.

ALL filters will do this if you leave them long enough.

In fact - you should change/clean your filter only when the pressure indicator says so (or you notice a performance drop). Cleaning it too often means you will get dirtier air getting to your engine.

Foam is pretty mediocre as a filter medium. The ONLY reason it is used for dirt bike and small OR engine filters is because of all the mud and water - a cellulose (paper) filter will get soggy and fail. Foam is almost as cheap as cellulose - the other option would be polymer (synthetic), glass or stainless fibres, which are much more expensive (and glass is prone to fracture with vibration).

Foam is very mediocre in terms of fitration performance. Only when it builds up a dust cake would it be working well.

It has been stated that you get a film of oil on your intake ducting. That oil will contain dust whether you can see/feel it or not. It takes a LOT of dust - or very coarse particles which are easy to capture - before you can see it in the oil. If oil from the filter is getting to the inlet then so is dust.

That is not to say that foam filters aren't suitably designed for MX bike applications. However it is flawed logic to think they would be suitable for a larger engine.

Round 2 fight!

Its a trade off, filtration vs performance.

I run a large uni filter, i know its not working as well as a paper filter but that is of little concern to me.

Make the choice on engine life vs engine power.

Z()LTAN wrote:Round 2 fight!

Its a trade off, filtration vs performance.

I run a large uni filter, i know its not working as well as a paper filter but that is of little concern to me.

Make the choice on engine life vs engine power.

You do realise how daft this sounds don't you?

"I know my filter is shortening my engine's life, but I'm not interested in fitting a large or efficient enough filter, despite the thousands of dollars and hundreds of hours I've spent on my car"

I have a foam filter that you are talking about, they have 2 layers and if not cleaned regularly they do clog up and if they dry out they perish. I see why they would be used on moto's as they would be easy to clean and you dont need an air gun or wait for them to dry. I wouldn't get one again and will go paper when i replace it. It offers no power gains if thats what you mean. Its a uni-filter.

Gwagensteve wrote:
You do realise how daft this sounds don't you?

"I know my filter is shortening my engine's life, but I'm not interested in fitting a large or efficient enough filter, despite the thousands of dollars and hundreds of hours I've spent on my car"

Shortening my engines life? I think 30psi heaps of fuel and a throttle jocky behind the wheel is doing much more damage than a few specs of dust ever will.

Like i said longevity v performance.

Gwagensteve wrote:

Z()LTAN wrote:Round 2 fight!

Its a trade off, filtration vs performance.

I run a large uni filter, i know its not working as well as a paper filter but that is of little concern to me.

Make the choice on engine life vs engine power.

You do realise how daft this sounds don't you?

"I know my filter is shortening my engine's life, but I'm not interested in fitting a large or efficient enough filter, despite the thousands of dollars and hundreds of hours I've spent on my car"

I don't think it's daft, as long as it's understood. Daft is when people run a shit filter but don't believe that it is shit.

chimpboy wrote:
I don't think it's daft, as long as it's understood. Daft is when people run a shit filter but don't believe that it is shit.

Fair point. You're right, that's a bigger problem.

Steve.

Z()LTAN wrote:

Gwagensteve wrote:
You do realise how daft this sounds don't you?

"I know my filter is shortening my engine's life, but I'm not interested in fitting a large or efficient enough filter, despite the thousands of dollars and hundreds of hours I've spent on my car"

Shortening my engines life? I think 30psi heaps of fuel and a throttle jocky behind the wheel is doing much more damage than a few specs of dust ever will.

Like i said longevity v performance.

I wouldn't be so sure. 30 psi isn't much for a modern DI diesel, and as long as your EGTs are sensible and you use quality oil...

The difference between a "performance" filter and a properly sized cellulose filter is barely measurable on a dyno.

Yeah how big is it going to have to be though i noticed a performance drop after installing my air intake system and its all 4" with a 7" x 8" x 4" uni filter. Couldnt fit anything bigger under the bonnet.

Z()LTAN wrote:Yeah how big is it going to have to be though i noticed a performance drop after installing my air intake system and its all 4" with a 7" x 8" x 4" uni filter. Couldnt fit anything bigger under the bonnet.

The donaldson G2 powercore will be no bigger than your existing filter:


Not cheap though, and pressure drop would be lower again if you fit a barrel style filter. Most modern trucks run 30+ psi boost. Any filter housing from a post 2005 5L - 7L truck should be fine.

ISUZUROVER wrote: The donaldson G2 powercore will be no bigger than your existing filter:


Not cheap though, and pressure drop would be lower again if you fit a barrel style filter. Most modern trucks run 30+ psi boost. Any filter housing from a post 2005 5L - 7L truck should be fine.

Would those filters work well on a non turbo petrol engine?

Matt_85Lux wrote:
Would those filters work well on a non turbo petrol engine?

yes

ISUZUROVER wrote:

Matt_85Lux wrote:
Would those filters work well on a non turbo petrol engine?

yes

Cheers

Have a look at aem dry flow filters from states

I just bought a paper filter for the scort,had the choice of foam or paper.So i went paper.