OK I have a custom cold air intake. What I did was buy 2 air intakes on ebay and clamped them togeather with minor mods and I have my air filter all the way down where on intercooler would go. My only concern is water. Can water get into my air intake? and if so what will happen if water gets into my manifold? Or should I get an AEM valve. I've had this for almost 6 months and had no problems in the rain. but i'm sure that water is getting on the filter.

and is there any filter out there that will stop water?

unless the filter is submerged it will be fine..

I'd get a bypass valve to be safe. It's much better than facing the consequences of getting water in the engine. Pretty much equals hydrolock and time to safe up for an engine rebuild. You can easily bend a rod if you take a substantial amount of water into your cylinders. Water doesn't compress so the weakest part gives ... the rods. It's okay that the filter gets wet but it's bad if a substantial amount of the filter gets submerged.

just don't drive through any LARGE puddles or like some flood waters.. I'd figure you'll be fine.
My uncle was taking his 300zx back from the coast and there was some flood water he had to go through.. everything was fine till a big truck going the opposite direction made a big wave that washed the water up to his intake *BOOM* he got a new engine after that.

So what does a bypass valve do? It's like $50. Let me know

Yes what does it do, I just heard that it prevents water from getting into the engine. And you also loose the sound of the intake if you put on the bypass valve, but I guess dats not that big of a problem.

lets see if I can describe how it functions ... it basically looks like a filter higher up on the piping. The intake will normally take air from your bottom (cold air) filter. If it is submerged it will take air from the other (bypass) filter. Think of it this way ...

Both filters are open air -> intake draws from the cold air filter (it's easier)

Cold air filter submerged and bypass filter open air -> intake draws AIR from bypass filter (it's easier than trying to draw water in from the cold air filter)

Both filters submerged -> um you're screwed and if water's up that high you got bigger problems.

Anyways, that's not the actual physics behind that but it's the basic idea. Regardless, don't go gunning it through standing water that would have your cold air filter submerged. Better safe than sorry. And you shouldn't be doing that in those kind of conditions anyway. :)

So for me which i have never been in a flood in my life, just regular driving with occasional rain it would be ok if i didnt have the bypass valve?

a little rain water is no problem... as some people used to tell me... a little water is actually healthy for the car.. it'll keep it cooler. And think about it this way.. the engine is so hot.. the water will most likely evaporate before doing any major damage.

So be smart... don't splash through puddles like a SUV.. and be senseable. You'll be fine.

My friend has an AEM cold air intake on his SI.. and he's been fine for a year now without a bypass valve.

just don't submerge it and you'll be fine as in watter go as high as 1/4 bumper or something. If you gonna go flood running keep the 2GNT in the garage and roll out the truck hehe. :P

hey, id like to hear more about your intake. if ya got pics, or have time to gimme the lowdown, hit me up on email.

thanks

dont worry bout it. just make sure you understood what everyone said.

well i was in a rush yesterday when i RE.. so heres my side of it

CAI for overa year or so now.. living in rainy ass florida.. its been fine.. one day my stupid ass hits a dip and hits the gas hard and in lots of water.. the car starts to bog a lil...

so i pull over outta the rain and shut if off.. turn it back on .. and rev it up and alls fine.

u will suck up a tiny bit of water buy mystic is right it will evap b4 it even gets near the car.. and dont some cars use water injection or something.. a lil bit of water will cool down ur car..

but they are right about the bypass valve.. once it senses low pressure (meaning filter in water) the lil slits in the valve open and it acts like a short ram.. so its taking air in from the Bypass valve..

i know one guy who hydrolocked.. with a CAI..it was a DX.ahha dont know how he wont admit it.. but my filter is near the ground and nothing so far