Maybe it's a snorkel and traps any water that gets sucked in

 

I would also like to know if i could remove this. i want the sound of an aftermarket intake but i dont want to suck up water and destroy my car.

 

I did it and a drop in filter...makes some audible difference. ..car runs fine

 

Was it easy to take out? Im considering doing this to my '15 next

 

You'll need to be in some deep water to suck it up. Just don't get a cold air...A few inches of water is all it takes for those. Blew my lancer a few years back from a monsoon in az. Will never do a cold air again

 

Ya undo 2 bolts and pull air box out

 

The sound will increase, moisture will be just as unable to reach the filter in normal circumstances as it was with the moisture trap installed. Instead, there will be a hole. Plug the hole. You want to keep the air path closed unless you are deleting the entire ram assembly.

A cold air intake on a WRX without a tune is going to run like dog doo doo.
A short ram intake on a WRX without a tune is a gamble, it may run flawlessly, it may run equally like dog doo doo.
Both have applications in the Subaru world, both SHOULD be tuned for, the differences are:
Short ram:
easy installation
less tuning required
less expensive
easier to service
less risk of water ingestion
Cold Air Intake:
quieter
less hardware in engine compartment
capable of a few more horsepower/torque in applications where this is necessary (typically 400+ whp builds)

generally, unless you are doing a huge turbo upgrade and have lofty power goals, a panel filter and deleting the entire forward intake assembly down to just the box, and replacing the inlet and MAF tubes are enough for anyone staying under 325whp by end of build.

I am saying that because aerodynamically the stock box is easily good for 300hp.
the hoses Subaru uses, along with it's labyrinth of an intake path can be swapped out for considerably more efficient and durable silicone hoses without having to be concerned about tuning issues or CEL code riddles.

The sound of a short ram intake is about the same as a fully silencer-deleted stock box w a drop in aftermarket panel filter.

hope this gets all the facts in a row for any of you guys shopping for parts.
you don't have to spend a fortune to get this part of the car up to maximum performance capability, and there's not a lot of sense going further without considering all the rest of the car's safety, like brakes and suspension, and the shock being applied to the transmission when upping the power by 30hp or more...

fwiw, a properly upgraded intake with correct tuning will net no more than 12-13whp all by itself, and that will be for a very small part of the car's overall power curve from 600rpms to 7200rpms. That power will make itself available though shorter spooling time in the compressor (earlier boost) and in off-boost, low end torque. Otherwise, the more extreme those two improvements, the worse other parts of the throttle curve will become, which is why tuning becomes necessary based on how extremely modified and shortened/velocity-increased the intake path becomes based on those modifications. This, left untuned-for, can lead to the ECU pulling timing and possibly even sending a limp code and causing the car to behave rather unkindly to it's driver until it is reset and correct tuning is applied. -again, fwiw (for what it's worth), not a warning, nothing wrong with brave advances with a car built with motorsport enthusiasts and hobbyists in mind.

 

i have done it one my wrx .. runs fine ..

 

CMEJATT - did you notice any significant sound difference?
I'm really tempted to do this - but if the sound difference really isnt THAT much, I'm not going to waste my time ripping that crap apart, ya know.

Impreza2.0 - that was a ton of info man - thank you so much!
Everyone mentions sucking up water with their CAI - have you seen the Mishimoto intake for the '15?
It looks like its sucking air from the engine bay / stock snorkel - so I don't see how water would really be an issue.
I have, however, seen some CAIs on other cars where they pull air from the fender well, which I could definitely see being an issue if you hit a decent sized puddle of water.
Also - you mention that you should really do a tune with the CAI - the Mishimoto product says it maintains safe AFRs with subarus stock tune - no tune required, but recommended to further enhance the setup.
Your thoughts on this?

 

It's not a cai if it's not sucking any cold air now is it? A true cai runs through the fender to get the coldest ait possible. Otherwise it's most likely a short ram

 

no difference in power .. just i hear the turbo spool up more lol.. thats about it.

 

I tried looking up some DIY vids but there are none for the 2015 and the 15 milk jug seems to be in a different spot. Do have to take out the plastic wheel well thing to access it?

 

id like to see a video of this as well. if theres no harm done i will do it to my 15 wrx as soon as it comes in as well.

 

Check this out:

This video is from Mishimoto, talking about the stock air intake system - this should clear up any confusion as to where exactly the milk jug is located, and how the whole intake assembly is put together.

2015 Subaru WRX First Impressions and Review by Mishimoto - Part 5 - YouTube

 

This modification is absolutely NOT necessary if you are running less than 300hp.

It does indtroduce more sound from the intake side of the engine into the cabin, so yes, it does make the turbo portion of the engine more audible.

If there is any increase in performance from this at all, and I would be surprised if there were, it would be in throttle response. Theoretically you are making the air path to the intake shorter and more efficient at the cost of more noise, but again, it is not creating more power, only allowing existing power to be more easily used. I am betting most of the 'performance increase' is the placebo effect of hearing the turbine spooling. Until you have ported every joint in the intake, and have the correct finishes established on the inner pipe surfaces, there will be little to no real provable power increases found on a measuring tool like a dyno. Throttle response increase and reduction of spool time are in many cases more useful than increases in power. Since power can be made to be available earlier with some of these modifications, it is not a sacrifice that there is no gain in horsepower... if you chart the engine, and see 280whp at 3100rpms instead of 3400rpms, the zero-sixty trap speed, or even 0-100mph will be significantly shorter.

It is easy to fool someone by saying you only have 300awhp.. they might have 400 to the rear wheels.

If your 300awhp is at 2700rpms and their 400 is at 6000, your car will walk all over theirs.
that doesn't even depend on the transmission type at that ridiculous point.

I hope this gets the point across that if you want to do all the other work that the intake cone sort of 'crowns', it's worth it, big time. On the other hand, it's stupid time consuming, and ends up forcing you to create a custom tune for yourself that inevitably will cost you in fuel, regardless of the benefits... staying stock with all this stuff is still totally good to go, all the way to 300hp, though the climb is obviously going to be steeper.

-agreeing w 11black, this stuff absolutely SHOULD have a tune either simultaneously or immediately following installation of a new intake system.... the engine computer is doing it's best to make the existing system efficient, offering it a more capable system and not giving it the headroom to make use of it is silly. It is a huge waste of money and can potentially cause long term wear that there is no need of. so my edit in this b - yeah. get a tune.

 

Just did this on my 2015 wrx, was fairly easy you just have to pull out half the airbox. Very minimal sound difference but i only drove for like 3 mins. Also threw a CEL with flashing CC. Says mass air level is low.

 

Did you...ughhh... plug the hole from removing the jug?

 

i used duck tape to cover the hole. i personally didn't hear much of a difference.

 

Ok now after driving a little more i can definatly hear the increased intake sound and bov slightly. Today i did a little experiment to see what it sounds like without a k&n filter, i drove al day with the stock filter and noticed no spooling/intake sound at all. Also for some reason i was only able to hit 57 in second gear no matter how hard i tried (i redlined multiple times). When i got home i put the k&n back in and went for a test drive, all the sounds returned and the first time i redlined in 2nd i manged to hit 60 mph. I think this is really weird cause i thought it was the gear ratios that determines the top speed you hit in gear???

 

It's a resonating acoustic plenum. The primary purpose is to reduce the noise with a secondary purpose to trap moisture.

 

I did this to my 2015 WRX. Once the "milk jug" is removed then resealed. It does not effect the audibility of the turbo. Just thought I'd throw that out there, just get a CAI..

 

i had my air box out yesterday but didnt remove the milk jug. it seemed extra hard to get it out, those tabs dont really bend much. i would have wrecked the whole thing if i had forced it out.

 

Has anyone purchased the HKS plug... May add resonance... http://www.subispeed.com/hks-air-intake-funnel-milk-jug-delete-2015-wrx-2015-sti#.VVVmNZ_n_qB

 

Has anyone purchased the HKS plug... May add resonance... HKS Air Intake Funnel (Milk Jug Delete) - 2015 WRX / 2015 STI

very interesting.. looks like a cool part.. for $100 though... tough to swallow.

and if you noticed... its discontinued..

 

I missed that.... Maybe ebay

 

So I removed the "milk jug" yesterday from my 16'. I did end up plugging the hole with a rubber cap I had in my garage and ran a few screws through the preexisting holes in the intake box through the plug to hold it in place.
Went for a short drive and didn't notice any change in sound whatsoever. Still very quiet and to me almost sounds quieter than stock.