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How To: CAI Splash Shield

28K views 43 replies 30 participants last post by  Arinzeuno 
#1 ·
Well, I wanted to get this done before the snow and crap came in, but the 34" of snow we've had so far in December had other ideas. Anyway, I had some time off for the holidays and the weather was nice, so I finally got this installed and did a little write up for you guys. :)

As a lot of you know, when you install a CAI, the filter is pretty much right behind the vents in the wheel well area. If you ever noticed under your hood, all the water and road grime/salt that comes through there splashes all over the CAI and up into the engine bay. I preferred to just keep my Injen CAI on all year up here in the northeast, so I figured a splash shield was cheap insurance against soaking the filter, and having to clean it much more often than a normal air filter.

I went to my local Lowe's looking for the right material, and found the perfect piece. It's a aluminum ducting tube that comes unrolled, and being aluminum and thin/flexible, it made it perfect for this project. It was thin enough to cut with household scissors, and stiff enough to hold it's curved shape. I wanted to have the shield mounted behind the wheel well vents in a curved manner so it would allow air in still, but any incoming debris/water would just hit the shield, drop down, and drain out the bottom. The piece was like ~$2. I also had some small black sheet metal screws around that fit the bill. Here is the piece of aluminum I used for the shield...



The first step was to jack the front up in the air via a floor jack and the front factory jack point, and remove the front driver's side wheel. Once you do that, you should see this...




You can see in that pic how close the filter is to the vent openings in front of the wheel.

The next step is to remove 4 philips screws under the front of the car, and the three in the wheel well itself...

Here are the lower screws...




Here are the upper fasteners. They are basically push in fasteners with screws in the middle. Once you remove the screws they should pull right out.

You have two to the left of the vents...




...and one more above the vent.




Once you get all those out, you should be able to peel back the vent part easily. Take the aluminum shield piece, cut it in half across the curve so you have two equal pieces. The 2nd piece is extra so if you mess up along the way you have a second shield piece. This part is pretty basic, but there is no one way to get it mounted behind the vent shield, so don't worry about doing it wrong or right. You basically just want the shield behind the vents in the wheel well, covering them, but curved so air can get in still. On the piece I got the underside was a gold color, so you can kind of see how I allowed it to curve over the vent openings. I just used four small, ~.5" sheet metal screws in each corner.

Here is the end result...






That's it...you're done! Just put all the fasteners back in, the wheel back on, and drop the car down. Now, you won't have to worry when driving around in a pouring rain, or if you live where it gets cold, water filled with road salt. Just to give you an idea of how much crap the filter gets, I put in my Injen maybe 3 or 4 months ago, and this is how my filter looked on the vent side...




..and this was how it looked on the back side...




Hope this helps anyone wanting to do this. It's a really easy, cheap project that will keep that filter nice and clean for much longer, and pretty much make filter soaking a non-issue while still allowing plenty of air into the fender well.

If you are putting on a CAI anyway, this is also a good extra step to do when installing it. Once it's in there, you can just forget about and drive...

:cheers:
 
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#2 ·
You need to buy a Injen Hydroshield for $25.00 for more security , The aluminium piece is good but your egine will not have the best air flow if you covering all the vents ..

Mine is 60% vents covered with the same part (aluminium) + the Hydroshield .
 
#3 ·
You need to buy a Injen Hydroshield for $25.00 for more security , The aluminium piece is good but your egine will not have the best air flow if you covering all the vents ..

Mine is 60% vents covered with the same part (aluminium) + the Hydroshield .[/b]
+1

Great write up but IMO a hydroshield is a must, as well as some sort of splash guard. I run with both and my filter still looks nearly new after 3 months.
 
#4 ·
The pictures may not show it well enough, but there is plenty of room for air the way the shield is mounted. Regardless, that area doesn't only get air from the wheel vents. It also gets some through the front of the bumper via the area around the foglights, as well as being open underneath the filter. It's not a sealed area only being supplied air via those wheel vents. Also, airflow is not an issue on this FI car even if those vents were completely sealed. The stock airbox setup pulls most of it's air from up under the hood.

The hydroshield is also an option, but not really needed with the splash shield IMO. You also limit airflow to some degree with an hydro shield...
 
#5 ·
The pictures may not show it well enough, but there is plenty of room for air the way the shield is mounted. Regardless, that area doesn't only get air from the wheel vents. It also gets some through the front of the bumper via the area around the foglights, as well as being open underneath the filter. It's not a sealed area only being supplied air via those wheel vents. Also, airflow is not an issue on this FI car even if those vents were completely sealed. The stock airbox setup pulls most of it's air from up under the hood.

The hydroshield is also an option, but not really needed with the splash shield IMO. You also limit airflow to some degree with an hydro shield...[/b]
good work Insane
if I still ran with a CAI, I would do this
 
#7 ·
Good write up. I actually bought a whole roll of thin siding sheet metal for like $10 at home depot and have a bunch extra. I took the whole wheel well out to make it easier. I made mine into a _|-------|_ like shape, bending the right angles by holding a beice of wood accross the sheet metal while it was on the ground and beding the mettal around the corner. But your way looks to work well and be easier.
 
#8 ·
+1 on the hydroshield. i would also reccomend a splash guard on the filter itself that wraps half way around because that way you dont lose airflow.
 
#9 ·
Good write up. I actually bought a whole roll of thin siding sheet metal for like $10 at home depot and have a bunch extra. I took the whole wheel well out to make it easier. I made mine into a _|-------|_ like shape, bending the right angles by holding a beice of wood accross the sheet metal while it was on the ground and beding the mettal around the corner. But your way looks to work well and be easier.[/b]
I thought of bending mine the same way, but I was losing daylight fast so I just did it by hand. The end result is what matters.

:)

+1 on the hydroshield. i would also reccomend a splash guard on the filter itself that wraps half way around because that way you dont lose airflow.[/b]
Again, you could completely block the vents and not have any problem with "airflow". This is a FORCED INDUCTION vehicle, and there are plenty of other open areas for cold air to get into that fenderwell area. The only thing that will affect airflow is the hydroshield itself. This is not a hydroshield or no hydroshield thread...it's simply a walkthrough for a CAI splash shield. Can we try to keep this thread on topic for a change? Thanks.

:)
 
#10 ·
Hmmm....good idea. I notice how large the openings of the vents were and wondered about the affects on the CAI, but that is about where I stopped, didn't come up with a solution so much.

I'll do something similar myself when i reinstall my CAI. Thanks.
 
#11 ·
i j/ used 3 layers of window mesh (cris-crossing) to REDUCE splash, not to eliminate splash totally...
been like that for +1 year, winter drivin' in canada also...no problem...however, i've recently bought myself the
injen hydroshield, cuz the filter still gets very dirty over 3 months~
 
#13 ·
Is that shield for when it's being used as a CAI? It looks cool, but it looks like it limits airflow quite a bit. Did you make that or is it something you bought?
 
#18 ·
Looks like that piece could be an alternative splash shield then. I'm guessing it costs more than $2 though right?

Either way, the end result is the same though...

:)
 
#20 ·
Insane -- Thanks for the How To. Did mine over the weekend and got an interesting side benefit (some may disagree though): I hear less turbo spool and blow off through my CAI. I know many like the BOV sound but it didn't do much for me (especially the spool). I have the Fujita which seems to be louder than most CAI's. Now, the sound is still there but muted.
 
#21 ·
LOL...I posted a thread on this summer 06 (same ducting even)...funny how things recycle. By the way the ducting does not really do well with the salt and I ended taking mine off last fall. I've been meaning to make another but never got around to it. Perhaps a project for this weekend...

Yours looks good by the way.
 
#22 ·
LOL...I posted a thread on this summer 06 (same ducting even)...funny how things recycle. By the way the ducting does not really do well with the salt and I ended taking mine off last fall. I've been meaning to make another but never got around to it. Perhaps a project for this weekend...

Yours looks good by the way.[/b]
Sorry, didn't see the thread. I guess I'll see when the spring rolls around, but I don't really see how the salt is going to do much to the aluminum. If you used steel ducting, I'm not surprised if it wreaked havoc. Even if it does, I have the other half still, and @ $2 for a piece that makes two shields...I'll live. ;)

Insane -- Thanks for the How To. Did mine over the weekend and got an interesting side benefit (some may disagree though): I hear less turbo spool and blow off through my CAI. I know many like the BOV sound but it didn't do much for me (especially the spool). I have the Fujita which seems to be louder than most CAI's. Now, the sound is still there but muted.[/b]

No problem. I've noticed that side effect as well, and it was a pleasant surprise for me too. I'm not a kid anymore, so less noise is always a plus. It hasn't cut back on the sound of my Forge BPV too much, but the whooshing wet dry vac sound has cut waaay back.

:)
 
#23 ·
With Insane as my inspiration, I built my own splash guard today for my AEM CAI. It turned out pretty good and it fits perfectly. Once installed, I still have about 1/2 inch clearance to "breathe" on the side of the filter that it protects.

Started with a chimney pipe, and drew my pattern
[attachment=34307:IMAGE_007.jpg]
Cut out the pattern
[attachment=34308:IMAGE_008.jpg]
Bent to shape
[attachment=34309:IMAGE_010.jpg]
 

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#25 ·
how much to make me one?
 
#26 ·
Very nice man. That's a hell of a lot nicer than the job I did...lol.

When the spring finally gets here and I do my spring cleaning/wheel swap, I may have to remake mine similar to yours. I'm also planning on picking up a dryflow filter for the Injen.

Excellent work!

:cool: :cheers: :thumbup:
 
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