Hey Fellas, I have a '08 MCSm that's bone stock, and it's time to replace the air filter, so I'm thinking about intake upgrades. First and foremost, I want to keep it CARB-legal so I'm not swapping parts every two years for a smog. Second, I don't care about the sound either way, I'm just interested in what I can do for HP and efficiency. I won't be doing much heavy modding beyond the intake, maybe just a cat-back and bigger intercooler (and a tune from Jan).

Is the JCW intake worth the money, or am I better off just upgrading the panel filter in my stock box? If the latter, K&N or something else? Are there other CA-legal intakes worth considering?

 

The stock intake is about the best you can do. Many aftermarket cold air intakes actually reduce horsepower, at best they make the same horsepower but are louder.

Dave

 

+1!!!

And sometimes you can lose power too. Hence that's why I went back to the stock box with a K&N drop in filter.

 

NM is the only CARB legal at the moment unless you count a K&N drop in filter.

 

That makes no sense. K&N has been proven time and time again to cause vehicles to lose power with their filters.

 

With a open k&n I can see that. I have a drop filter and didn't lose low end like I did with an open, so if I did lose any, maybe 3-5hp, which I can sacrifice since I got the JB and DP on.

It's not like I said I gained 10hp....

 

The K&N Typhoon Intake for the n14 is CARB legal as well, it comes with the CARB decal.

 

Your best options are to go with a high flow dry panel filter, or the JCW intake. The dry panel filter won't put any oil through your sensors keeping your warranty intact. The JCW will give you more torque and keep it quiet still.

 

Okay, I think I'm ready to spend the money on the JCW intake. Of course, it comes with a paper filter, which I'll have to replace eventually. As long as I'm under the hood, I might as well replace the restrictive paper filter with something reusable. So far I've found 4 filters to fit the JCW airbox:
ECS Tuning sells the Pipercoss filter, a no-oil foam filter.
MiniMania has a "Performance cotton" filter, as well as this "Air filter replacement upgrade". Looks like it may be the same one sold by Madness.
There's also one made by ITG in the UK. looks to be a foam/oiled cotton hybrid.

Anyone have experience with any of these? I know there's a concern about filter oil fouling the MAF sensor, but from what I understand, oiled cotton filters breathe a bit better than dry filters. Is it possible to oil a cotton filter lightly enough that it won't spit oil into the MAF sensor?

 

I've personally run the Pipercross filter in my JCW intake and had zero problems with it.

 

i have used oiled filters in just about every car i have owned(5 in the past 2 years since i turned 18) and i have never had any issue with MAF sensors going bad

 

I really question a properly "oiled" filter causing problems w the MAS. I've heard this for years but... never seen an assoc. failure in the past 7 years being a automotive service manager.
I just lightly oil it then use compressed air and blow the heck out of it before I install.
BTW I have a 09 JCW with a DDM race intake for double the fresh air fun.

 

The oiling issue with MAFs is typically, the end-user over oiling the filter after they've cleaned it and then oil residue ends up on the MAF sensor.

Not hard to avoid if you pay attention when re-oiling.

Now. Crap. I just ordered a K&N RE0910 cylindrical filter for mine. Its the one that fits inside of the stock lower airbox, which will still get cool air from the stock location and then whatever air blows over the engine from the scoop. Will I lose power here?

I had debated between that and a K&N panel filter that fits in the stock box.

 

OK, you guys have put my fears to rest. I had a K&N in my Civic for about 6 years and never destroyed the MAF sensor. I think I can be careful enough not to over-oil it.

broncobuddha, I've seen a ton of debate here and elsewhere about the open-air "cold air intakes" for the R56. Lots of people point out that the stock intake sucks from outside the engine bay, while the open-air types, like K&N's intake, will actually grab hotter air from the engine bay, and this could lead to a loss of power. Others maintain that at highway speeds the air in the engine bay is no hotter than outside, and the open-air intakes have better flow and a shorter intake tract. I think I might do some smartphone-dyno runs with the stock airbox lid off, see if the car gets slower sucking engine bay air.

When you get your K&N RE0910 cylindrical filter, would you mind taking a few measurements for me? I wonder if it fits in the JCW airbox. If so, it would be the cheapest option by far.

 

Here are the measurements for the K&N:

Length (in):8.000 in.
Inlet Flange Inside Diameter (in):3.000 in.
Air Filter Top Measurement:4.625 in. diameter
Air Filter Bottom Measurement:5.000 in. diameter

This should let the filter actually sit in the stock lower air box. Which means, it will pull cold air from the stock location.

Now, that leaves the upper portion of the stock box off and the top half of the filter open to pulling air in from the engine bay. I would hope that at any kind of speed, that cool air would come over the engine from the scoop. (My scoop plug has half a dozen or so of the grid holes opened up, i would merely open the rest)

I actually cancelled my order on Amazon, as I'm researching filter choices some more. Not sure I want to go this route, get a K&N panel filter, or a foam panel filter from Alta.

I was starting to think maybe Alta's foam 2.75" filter might work as I described above but I'm not sure.

I'm not in the market to spend the kind of funds on a whole intake system at the moment, so, I'm just looking at filters.

 

There used to a CAI from Defenders of Speed that drew air from the high pressure around the base of the windscreen. Nor sure what happened. IMO I think that setup combine with a functional air scoop to cool engine is best. I DO feel hot air drawn over the engine is NOT a good thing. My JCW has an excellent CAI setup. I've been debating on removing my DDM race intake for this very reason. Things get way hotter under the hood than ambient temp and having cooler air running over the motor seems like a better logical choice.

 

If I remember correctly, the top of the stock air box can't be taken off and left off because that's where the MAF connects to. So if you left the top of the box off, you'd throw all sorts of codes cause the MAF wouldn't be doing it's job properly.

 

I believe doing it that way, you have to add a 90* elbow and just move the MAF after the elbow as the air straightens out.

Wouldn't that work?

 

The bottom of the intake box receives the air from the intake scoop at the front of the car by the driver's headlight. This air then flows through the filter and then through the MAF on down into the turbo. If you left the bottom of the box in car with a filter in it, and took the top off, the MAF would have no source of filtered air to feed into the turbo. That's what I was getting at. The system wouldn't be closed if you will.

 

You relocate the MAF as it will no longer be attached to the upper box.

In every case I've seen where either the stock box is replaced/removed, relocating the MAF is done.

I know I'm not the first one who's done or tried this. I just can't think of the link for where I'd seen it.

 

Chiming in here, but there is proven data where an open filter alone increases HP, check the Alta thread regarding this. Yes the closed filter gets cooler air, but it is a fraction of the amount of air being taken in the system. I personally saw only an increase of 2 max of 4* with stock airbox vs my Alta open filter. I will take that to ensure I am getting as much air as possible to my little power plant.

The real culprit is the location of the airbox/intake. Even with the stock airbox (plastic) it still sits right behind a hot engine, a compressing turbo, and above an exhaust system causing IAT about 20+* above ambient. If you really want to see some cool numbers, ceramic coat the DP! Since I have installed my ceramic coated DP, I rarely see more than 5-8* above ambient once underway.

 

Until we see dynos from people with just a "CAI", I've only seen losses of hp(felt is more like it).

 

Well I felt more with just mine on lol. Here is Alta's website with info from their dyno on a stock MCS/JCW showing the HP increase:

http://altaperformance.com/i-1400715...bo-engine.html

 

Here is an interesting Youtube video in which they dyno a car with different cold air intakes. The stock one was the best.

 

I have a K&N RU3130 at $29.XX right now on my JCW CAI... Very happy with it. I am due for a replacement and will try Amsoil blue paper filter from Detroituned maybe slightly double the $$ but it's paper and no worries.

Good luck on your search!