Foam Filter

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Thought I would start a new thread relating to foam filters...

As I am trying to decide between paper/cotton gauze style filter... I came across a company in Australia called Uniflow.

They make foam filters for vehicles.

I tried to do some research online... apparently foam filters filter the best and due to the cellulose nature of them they also provide air flow as good as cotton gauze.

So it is like a K&N air filter in terms of air flow/performance but filters much better (or better) than even paper filters.

Anyone know anything about these?

According to this: http://www.uniflow.com.au/contents/en-us/d358_How_Unifilter's_Work!.html

It is a no brainer...

Anyone?
 
I can tell you that Uni is all I use for my motorcycles, dirt bike, and scooters without any issue.

I'm pretty sure there isn't a dirt bike made with any other kind of filter.

I'd be hard pressed to believe they filter better than the best paper filters, but I would believe they have an advantage in flow and at least match them.
 
I am also very interested to see what people think of this:

http://blog.perrinperformance.com/foam-filter-qa-why-they-are-the-best/

How much truth is there to this?

I been reading K&N's 'facts' page about how filters work and why they do work better than paper etc (independent lab tests and bla bla) and they got a nice diagram why foam filters are bad compare to theirs...

Those exact diagrams are on the page I just posted and explanations of why that is dribble about foam filters etc...

Anyway, if someone can scan through that link... how much truth is there to it?

If Foam is going to at least filter as good (maybe a touch worse) than paper but definitely a lot better than cotton gauze and still flow as good as a K&N... then well I would go that. I get the benefits of both without sacrificing either.
 
Used on every dirt bike since the begining of time. They collect more dirt than any paper filter I've seen. I used to service quad bikes, in every 3 months, and the foam filter was always a mess, covered in dirt.
 
Originally Posted By: Wreckage

I tried to do some research online... apparently foam filters filter the best and due to the cellulose nature of them they also provide air flow as good as cotton gauze....



It is a no brainer...

Anyone?


Not knocking foam filters, in fact I thought of making one from an old mattress a while ago but was too busy.

However, while it MIGHT be possible to make a foam filter from cellulose, it'd be difficult and I'm fairly sure no one does.

I think they're usually polyurethane.
 
You can buy filter foam in sheets, I've often made new ones when an old foam filter goes rotten and falls apart, and is not made anymore. They need more maintenance than paper or K&N, and it's a messy job.
 
Originally Posted By: Wreckage


Anyway, if someone can scan through that link... how much truth is there to it?

If Foam is going to at least filter as good (maybe a touch worse) than paper but definitely a lot better than cotton gauze and still flow as good as a K&N... then well I would go that. I get the benefits of both without sacrificing either.


I'd say they tend to exaggerate the performance and fuel economy impact of filter restriction, which actual measurements show is rather limited, but I suppose you have to do that if you are selling a "performance" filter.

I was thinking I'd "get the benefits of both without sacrificing either" by using both, running my DIY foam as a prefilter. That way I shouldn't be able to screw up too badly.

I have some doubts about the washability thing with a single stage filter. Seems it'd be quite easy to transfer relatively coarse damaging particles from the outside to the inside if you weren't ultra careful.
 
You DO realize there was the mother of all amateur air filter studies posted right on the front page of this site yes?

Long story... both the gauze and the foam let more dirt in than a good paper. On a dirt bike this is moot anyways since the most important thing is how often you can replace with a clean filter. Which at OEM prices would get really expensive fast every few rides!

In a street vehicle not worth the time. Use a disposable filter. Especially when you consider that modern OEM filters aren't really plain paper anymore, they're doing this "fleece" thing that probably works the best. AAAAAND the air box has been optimized to squeeze every last drop of power and FE from the motor.

Warranty? It's a heck of a way to lose coverage for related issues. Everybody likes to quote the Magnuson Moss warranty act but they quote it incorrectly.

In short: vehicles have LIMITED warranty, which offers a surprising amount of legal loopholes. Also while an OEM cannot force the use of a particular BRAND they are more than welcome to deny a claim for using parts not meeting SPECIFICATION. At that point (especially with the arbitration agreement) you are essentially S.O.L.
 
Wreckage,

I have a lot to say about all filter types - but I must ask, what are the goals you are trying to achieve?
1) Cost,
2) filtration, or
3) flow?

You can ONLY pick 2 of the 3, BTW.....
 
I had a Dolmar/Makita gas powered concrete saw that had an air filter that had a foam pre-filter, and a pleated paper filter. I cleaned out the foam pre-filter after every job and blew out the pleated every once in awhile. I only replaced the pleated filter once in 14 years. No problems in 14 years, lost it in the Hurricane Matthew flood.
 
Originally Posted By: Linctex
Wreckage,

I have a lot to say about all filter types - but I must ask, what are the goals you are trying to achieve?
1) Cost,
2) filtration, or
3) flow?

You can ONLY pick 2 of the 3, BTW.....


Well to keep it short...

1 and 3 so that I can enjoy the car more for the life it will have.

Having said that...

Most people I know that have toyotas have over 600,000-700,000 km on their engine and the car is still good. That is 435,000 miles on paper filters.

So wanting an alternative for flow and cost (reusable), ho much of that life will I prematurely wear out (if it even will?).

If I will lose 200,000 miles off the life of engine using foam/K&n then I will stick to original. If it will only be 50,000 miles, then I prefer the flow/cost (option 1 and 3)
 
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Originally Posted By: Ducked
Originally Posted By: Wreckage


Anyway, if someone can scan through that link... how much truth is there to it?

If Foam is going to at least filter as good (maybe a touch worse) than paper but definitely a lot better than cotton gauze and still flow as good as a K&N... then well I would go that. I get the benefits of both without sacrificing either.


I'd say they tend to exaggerate the performance and fuel economy impact of filter restriction, which actual measurements show is rather limited, but I suppose you have to do that if you are selling a "performance" filter.

I was thinking I'd "get the benefits of both without sacrificing either" by using both, running my DIY foam as a prefilter. That way I shouldn't be able to screw up too badly.

I have some doubts about the washability thing with a single stage filter. Seems it'd be quite easy to transfer relatively coarse damaging particles from the outside to the inside if you weren't ultra careful.


I agree they overstate.

I see no independent testing to support the claims UNI are an advantage and they are a PIA to clean compared to my quality paper filters which I simply remove and toss out. If UNI is so great then which high dollar sports car manufacturers use them in their cars?
 
Originally Posted By: exShuttlemech
I had a Dolmar/Makita gas powered concrete saw that had an air filter that had a foam pre-filter, and a pleated paper filter. I cleaned out the foam pre-filter after every job and blew out the pleated every once in awhile. I only replaced the pleated filter once in 14 years. No problems in 14 years, lost it in the Hurricane Matthew flood.


Well this is great news for everyone that drives a gas powered concrete saw to work.
grin.gif


But maybe diffcult to equate it in practical terms to a vehicle.
 
The best filtration is provided by a Donaldson PowerCore filter, which is 99.98%. However, OEM paper filters do generally filter well. If you aren't using a restriction gauge, you are probably changing your filter far too early, driving up the cost. I'd run factory unless I was putting in a Donaldson. Change it based on the filter minder/restriction gauge.
 
Originally Posted By: ArcticDriver
Originally Posted By: exShuttlemech
I had a Dolmar/Makita gas powered concrete saw that had an air filter that had a foam pre-filter, and a pleated paper filter. I cleaned out the foam pre-filter after every job and blew out the pleated every once in awhile. I only replaced the pleated filter once in 14 years. No problems in 14 years, lost it in the Hurricane Matthew flood.


Well this is great news for everyone that drives a gas powered concrete saw to work.
grin.gif


But maybe diffcult to equate it in practical terms to a vehicle.


Dust is dust. Ashes are ashes.
 
Originally Posted By: Corelokt
I only drive my gas powered concrete saw to church on Sunday once a week.


Sermon that borring? lol

Well I spoke to uni filters tech... this is what I got

"Foam filters will filter down to 4 microns. (This is why dirt bikes only use foam air filters) there is no better filter media available. Air flow across all filter medias is very similar. Results can vary between all medias depending of the filters application. Filter medias have changed significantly since the 1960s. They all work in different ways. The only true way to test filters these days is field testing."

So basically if i want engine for max air flow at the sacrifice of filtration - cotton gauze.

If I want efficiency and dont care to clean filter - Paper/oem

If im happy to clean the filter, have almost as good air flow as cotton gauze initially (better as the miles add up as cotton gauze clogs up and ends up less so than even paper) and still have Paper like (or better) filtration, - Foam

If that is about right in general...

then what is the deal about turbulant air going into the engine which foam due to the nature of having all those turns causes? Far as i know they all cause turbulant air anyway unless you get a flat screen which filters nothing.
 
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Originally Posted By: Wreckage
...
"Foam filters will filter down to 4 microns. ..."
That claim strikes me as essentially meaningless without further qualification. If 99% of particles that size get through, but 1% are captured, then the foam is "filtering down to 4 microns," to some extent.
 
Originally Posted By: CR94
Originally Posted By: Wreckage
...
"Foam filters will filter down to 4 microns. ..."
That claim strikes me as essentially meaningless without further qualification. If 99% of particles that size get through, but 1% are captured, then the foam is "filtering down to 4 microns," to some extent.


You were thinking what I was. "Down to 4 micron" could be anything lol.

Upon further investigation I came across this... an independent test done by one of our magazines here in Australia.

http://www.uniflow.com.au/contents/en-us/4WD Action Air Filter Article.pdf

I also realised through more research... Unifilter Australia is not the same as Unifilter made in USA. This product is made here in our country for our dusty/sandy conditions and should not be mistaken with the USA Unifilter.
 
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