Can someone try this simple little mod? In the picture below, can someone try the following:

Remove the airbox cover, duct-tape the square hole, put it all back and head to the road. In 3rd. gear, at 30mph, go WOT till maybe 65-70 (depending on your interstate speed limit - I'm not responsible if you get a ticket, ok? *grins*). Actually, try it before the mod and try it again after that.

Let me know if you feel any difference. Thanks.

 

ham,

I'll give it a whirl. I've been planning on cutting up the stock airbox hondata-style
anyway, so I can try this when I do. Only thing is, I don't know when I can do
it - this weekend perhaps.

The WRX guys typically remove an intake resonator from their wheel well. The
car has a stock air "ram" style piece of plastic that leads to the wheel well, where
there is a box that looks like a gallon jug. That jug is then connected to the air
filter tube. Removing the box provides little to no gains, but you can hear the
turbo spool quicker and more of the stock BOV. Just a FWIW, since these cars
are obviously different, but I don't know if we'll see much of a performance gain,
just more of a sound gain.

 

Yeah more of a sound gain if anything. But I will try that I always looking for a way to make my car sound beasty. So all i have to do is just duct tape that sqaure up then throw the box back on to stock form right?

 

Ill give it a shot, too. I have already removed the "vanes" from around the filter on mine, and polished it down as clean as possible where they were.

 

I too thought it might be just a sound change since I didn't know what what chamber was. But I was told it is a resonator chamber. Anyway, I taped mine up but I didn't notice any change in sound. But I notice a change when I go WOT in 3rd. at 30mph onwards. But I'm not sure if it is just me. Most intake guys will tell you there's a seat in the pants feel coz' of the roaring intake sound or really loud exhaust.

In this case, there's no increase in sound and I did feel something. Let me know if you guys feel the same.

 

Whats that realy supposed to do for you? I figure it would probebly drain a little horsepower wouldnt it? isnt that the only why for the air to get through?

 

That little chamber is an isolated air pocket on the way to the main chamber. There's just a square branch from the main tube going into it. Who knows what Honda figured the dynamics are in doing that, but it may just be there to dampen the noise.

I wonder if its better if the tape is placed inside the tube, over the hole that branches into that chamber?

 

It would be easier for Honda to make the box w/o the branch. One less part to attach. So, the branch has to do something. Maybe to lower noise further. But interestingly when I taped the hole, I did not notice an increase in sound.

It would be interesting to see what the pressure levels inside the airbox stock, w/ the hole taped, branched removed, branched removed and taped, and a full out Hondata airbox mod.

 

did you guys also remove that rubber/ plastic tube connecting to the airbox?... ne whoo i thought that, that was the resonator. I took that off only and i noticed sound diffrence at wot at around 2500- ?? rpms

 

I don't think you want to remove that plastic piece leading to the airbox. That's not the resonator. It's the intake tube. It channels *cool* air into the airbox from the side of the radiator. If you look carefully, you'll notice it is grabbing air not directly behind the radiator, but just a little to the right of the radiator on the side (if you are looking from the front of the car).

By removing this tube, you are just sucking hot air from the radiator and I believe you'll loose some power.

On ephatch.com, silverstream removed this intake tube and snorkel, fabricated his own tube and is getting cool air from underneath the car. My plan is to do the same since it is a cheap alternative and it will be a poor man's Comptech Icebox.

However, I'm skeptical about opening up the airbox by cutting up the walls ala Honadata airbox mod. If I can get pressure reading by doing this minor changes before cutting it up, I'll know for sure. But time is not permitting

 

I dont know how easy it is to get a digital barometer... I'll look around though.

 

Been there, done that.

I actually gutted out the entire stock box, including some of the top portion. All of the fins, and the entire dividing wall i removed. Then i duct taped over the resonator opening. This was used in conjunction with a K&N drop in filter. It was a pretty good setup. It drove a lot better then an SRI. You can actually feel the difference between a fully stock box when you hit vtec.

But now, i have upgraded to a Comptech Ice Box. Let me tell you, compared to my last setup, there's a big difference in throttle feel; it's better now! The midrange has also increased dramatically. "Fitment" is a little under par for comptech, but the performance side made up for the somewhat poor fit.

Good luck with your DIY stock box.

 

sjracer - thanks for sharing your info. I could gut the box entirely (even the little tube inside the airbox) like what Hondata did. But I want each change to be small and documented. Well, probably all these little changes doesn't do much, but it is good to know what help and what didn't. So rather than just gutting the whole box, it would be better to make incremental changes. Only downside is when you go the wrong way, you can't easily undo the changes

It would be interesting to compare a properly modified OEM box to that of the Comptech Icebox. Of course we'll have to re-route the cool air for the OEM airbox as well. Silverstream on ephatch.com did that actually but there's no testing done comparing OEM vs. modded unfortunately.

 

I also did the whole Hondata airbox mod and dropped in a Comptech Hi Flo air filter. Small difference until I got up past 5000 RPM, maybe the K20A2 will have a bigger gain. Intake sounds almost stock, much quieter than the SRI I also have but the SRI pulls much better until the weather gets hot.