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Discussion Starter #1
I am doing the stealth intake mod tomorrow on my 2005 ST. I searched all over town and the best k+n filter I could find is the 3 inch inlet. The filter just seems small. Is this going to restrict more flow than a larger k+n filter? Also I heard the 3 inch inlet is very tight, now being very tight, is the plastic intake piece that it goes on sturdy enough that it will not deform? Thanks.

http://www.knfilters.com/search/product.aspx?Prod=RU-3580


this is the filter i believe
 

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Filter looks good to me. If you think about if if you unrolled the filter media you would have more surface area for air to enter than most panel filters out there. The MAF tube is sturdy as well. You shouldn't have a problem.
 

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Some stores sell a multi-fit filter, it should have rings in it to go from 3-3.5-4". I'm fairly certain I had to take one ring out, and it's the 3.5".

I might be wrong, it's been a long time, but you'll know which one it is when you go to fitting it.
 

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Discussion Starter #4
it looks to me like the filter I am getting would roll out into something about te size of a panel filter that would fit in my air box. I plan on buying it this afternoon for $40.
 

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Discussion Starter #6
I have the filter now and I am going to put it on after 4:00 when I'm done studying for the day. I will post the results!
 

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When i changed the filter on my intake, i went and bought a K and N filter, that filter that you shown is small so i up graded to RE-0930, its a inch taller and fits perfectly for me.
 

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You can call K&N and get the CFM flow for the filter. It should be twice the maximum engine CFM at the minimum. This is so you can 'loose' up to half of the filter (dirt,crud etc).
 

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Some stores sell a multi-fit filter, it should have rings in it to go from 3-3.5-4". I'm fairly certain I had to take one ring out, and it's the 3.5".

I might be wrong, it's been a long time, but you'll know which one it is when you go to fitting it.
[werd]

i actually used one of those before i converted my system to my Stealth CAI mod part 2. the 3 inch is too tight.
 

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Discussion Starter #10
Well I have had it on for a day now. The intake noise didn't get much louder...just a little bit. At first I thought the car was slower...but I am assuming the computer adjusted for it and now I feel a very slight improvement. Raced my friends b16 hatch before the mod and after...he says it definitely made a difference as are cars are close to begin with....or I got better at driving lol. The 3inch inlet is extremely tight and I almost wonder if its not putting too much stress on the k and n's rubber.
 

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I have some focus engine building book and remember they tested filters. They had a turbo'd focus and tried a big and small cone filter and there was no difference in power output.
 

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You should get the K&N pre-charger to put over the filter- OR loosely cover the filter with panty hose to deflect water spray. From my personal studies, the panty hose does not reduce the effect of the filter regardless of how loosely you apply it. I put it on just tight enough to keep water from pooling in the valleys of the filter.
 

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What about filter length? I am thinking about an S&B Inverted Cone High Performance Air Filter 3.5" inlet x ?" filter media off Ebay. Would 6" be too long and hit the splash guard? Should a longer filter be installed? I think BlazingCoppers example is perfect, but I dont know the length of the filter.
http://www.ineedawebsite.com/BlazingCopperZX3/Stealth CAI.html
 

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I have a K&N 3.5" filter I used on my stealth intake for about 5,000mi for sale. PM me if you are interested. It is in perfect condition and it fit inside my stock '05 ST.
 
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