I had the same thought when I put mine on. I monitored the MAF with my AP and the reading was exactly the same with and without the prefilter....

I think its funny that people are questioning the "sock" term and if that is what its really called.
But if you look at the 5th post, I attached the AEM build of materials and it says 9" Filter Sock!
And it even has the AEM part number so you might be able to call them and order the sock separately.

does anyone know the dimensions (top diameter bottom diameter and height) of the filter i cant measure mine coza my bumper so i need those to order the filter any help would be appreciated thanks

^You can remove the filter without removing the front bumper.
Just remove the screws for the undertray (just the front screws), loosen the hose clamp for the filter, and lower the filter out the bottom between the undertray and the bumper.

^thank you jon.

^That little trick came in handy the couple times I cleaned the filter. ;)

lol, how often do you clean it?

I cleaned it after two years, then cleaned it again after water saturated the filter.
I've since sold my AEM, but every other year should be fine unless you live in a real dusty part of the country or just want to keep the filter really clean.

I'm lucky to have SummitRacing right down the road so I bought the AEM cleaning kit there, but you can also order it online:
http://www.summitracing.com/parts/AIS-21-110/
And its really easy to do, just takes awhile to air dry.
So cleaning it once a year isn't a pain unless you're really laze ;)

lol. whats the diff between the aem and the one that mazda speed has?

Probably nothing.

yeah thought so. they say its legal in cali (so they say)

AEM has a nice little guide that I like on how to properly clean the filter:
Attachment 143872

nice. im hopeing to get the k&n Typhon . but i heard its really loud.

I have blown a motor from sucking in water but on a different vehicle/intake design. The way the MS/AEM intake is it won't have a problem with water you'll be fine. If anything happens to the motor just put the sock on before you bring it to the dealer. The motor that blew, the filter was 6 inches from the front tire getting splashed on all the time and about 4 inches off the ground. Only blew when I entered a flash flood area and I blew a connecting rod out the side. Wasn't cool.

^ dam that sucks ...

as for the typhoon i wouldnt recommend it the aem concept is better you just have to have the balls to put it on there and not be scared of water lol

right by the tire? did they say anything?

I agree. You'll be much happier with the AEM.
Shouldn't be scared of water with the AEM.
Worst thing is some water reaches your MAF and your engine will make a bogging sound (which is scary the first time you hear it).
Don't be scared of rain or car washes, just avoid spraying directly at the filter.
You can play it safe and put a plastic bag over the filter when you was the car.

cool.

i have a typhoon and i like the sound of it, its the only sound mod i have since i still have the stock cat/exhaust. I think it sounds good.

^ listen to my aem youll like it better ;) lol jk i just like the concept of aem better no hot air

my car came with the typhoon, i would love listen/try other ones when i have the money.

hows the Typhon? ^ like it?

Pre-filters (or "socks" if you will) don't really help with water since they aren't very absorbent (they'll absorb a splash from a puddle but is that really going to hurt your engine anyways? Doubtful)...that being said...on all CAI's I have EVER used on pretty much EVERY car I have owned (except my Navigator), I have NEVER used a pre-filter or a bypass valve...and I have never even had a close call in any of them(even the Focus SVT, that had a CAI that put the filter about 5 inches from the ground).

we should meet up you can see how my aem sounds

that would be cool, i wonder when the next houston meet up will be.