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I have a set of HKS foam filter's on my GTR.

Being used to dirt bikes, i always wash, clean and reoil my foam filters. But apparently these have a "dry" type filter element/foam.

How the hell can a "dry" piece of foam filter out all the dust? Doesn't it need oil?

Before i just go out and clean my hks foam filters and oil them.

Is there any particular reason why i should not?

Obviously don't over oil them... I just spray a light coating on a nice clean air filter and thats it (dirt bikes).

Just having a dry foam filter in my car makes me feel so uneasy.

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I have a set of HKS foam filter's on my GTR.

Being used to dirt bikes, i always wash, clean and reoil my foam filters. But apparently these have a "dry" type filter element/foam.

How the hell can a "dry" piece of foam filter out all the dust? Doesn't it need oil?

Before i just go out and clean my hks foam filters and oil them.

Is there any particular reason why i should not?

Obviously don't over oil them... I just spray a light coating on a nice clean air filter and thats it (dirt bikes).

Just having a dry foam filter in my car makes me feel so uneasy.

Do you have air flow meters with a heating element on said dirt bikes? The problem with wet-filters is the oil often gets onto your AFM's heating element which will cause you problems. Modern dry-filters are very very good, there is really no need to oil. For example, the AEM dryflow filter has proven 99.52% filtration efficiency. Most brands of filter (Apexi, K&N, HKS, Injen, etc) these days will be much the same, there's no gimmicks.

Do you have air flow meters with a heating element on said dirt bikes? The problem with wet-filters is the oil often gets onto your AFM's heating element which will cause you problems. Modern dry-filters are very very good, there is really no need to oil. For example, the AEM dryflow filter has proven 99.52% filtration efficiency. Most brands of filter (Apexi, K&N, HKS, Injen, etc) these days will be much the same, there's no gimmicks.

true.

I have a map ecu and therefore no afm i run a very very large unifilter cylinder pod filter thing and I oil it, sucks a little bit in but nothing to worry about unless you have afm's.

I do have AFM's, the GTR is pretty much stock other then a hiflow cat/quiet exhaust and the hks pods.

I cleaned my AFM's on Sunday, who would have thought they are ment to be red and not black? haha.

I understand oil can get through the foam, but wouldn't that be if you over oil it?

I am only thinking about oiling them because of the bad rep the HKS filter's have...hence the third post on this thread >_<

Edited by Booki

I do have AFM's, the GTR is pretty much stock other then a hiflow cat/quiet exhaust and the hks pods.

I cleaned my AFM's on Sunday, who would have thought they are ment to be red and not black? haha.

I understand oil can get through the foam, but wouldn't that be if you over oil it?

I am only thinking about oiling them because of the bad rep the HKS filter's have...hence the third post on this thread >_<

I would just get new air filters.

I dont totally squeeze mine out, more so like i'd do on my bike, but if you squeeze it out real well it'll be fine id say clean your afm's as a part of your service sched..

Yeah definitely. Cleaning the AFM's will now be part of my sched. Seeing as i have only had the car for about 20 days, i figured it would be a good idea to start checking things out and seeing what needs to be done. Looked like the prev owner had never cleaned them.

I have nice spread sheets for all my maintenance records for all the bikes/cars i own :)

I know alot of people over oil there filters, hence them throwing off afm sensor's.

I think i might give them a very thin oil coat and a wash and just keep my eyes on it to see if it lets any oil through.

I have over oiled my air filters on dirt bikes before when i was new to them. But you get a good idea on how much is too much and how much is enough after you have done them enough times.

Hks filters are crap. Might as well not run one

I am actually interested to know why you think that.

I have read it alot, but havn't really seen any hard evidence on why they are bad.

Only reason i can think of is because they are "dry" ;)

On a completely unrelated note to this thread.

I checked my power steering fluid (least i think it is, the container near one of the AFM plugs), is a bit low.

Should this be changed out or just topped up? if so does the GTR take a particular type of fluid? Or can i just grab the generic stuff from super cheap.

If it needs to be changed, is it hard to do?

I am actually interested to know why you think that.

I have read it alot, but havn't really seen any hard evidence on why they are bad.

Only reason i can think of is because they are "dry" ;)

The HKS Mushroom filters don't get called "Poisonous Mushrooms" without due cause...

They tend to break up and send shit through the intake if you don't inspect them at each service to ensure they aren't stuffed. I've seen the inside of one, wasn't cool.

Take this chance to either

1. Get a stock airox which will be better

2. Replace them with Apexi or similar, and build a proper CAI box.

Both will offer far better reliability, and increased performance over rubbish exposed pods. Win-win really.

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