After searching and reading every thread about modifying the stock air box, I finally decided to "just do it." Thanks especially to Turtle and Fletch for their excellent contributions and pix. I used a Dremel (at max speed & with a router bit) to remove the half partition flush to the bottom of the box. From my research, water isn't real problem unless you actually drive through standing water that rises above the grill. I also enlarged the two drain holes by 50% "just in case." Next I cut out the partition on the top half of the box as well as the air guides and sanded the rough edges. Basically, I "gutted" the inside of the box. I also sealed off the opening to the air box resonator. Next I cut a circular two inch hole in the box (passenger side) and just in front of the horn. I then fitted a hose (old Dyson vacuum type) into the opening and routed it forward just behind the headlight and down to the underneath bottom panel and out one of the openings. My rationale for a secondary air vent is based on back pressures and having another air inlet for greater internal pressures such as during heavy accelerations. In theory, it should also tune the resonances. If it didn't or I didn't like the sound, I could always re-seal the opening. I'll post some pix as soon as I can get my wife's camera. The induction sound is great. Not nearly as loud as with the air box open, but much like a friend's K&N CAI. Throttle response is just a bit quicker (nothing really measurable), but the response over 5.5K rpms is real. My initial check on gas mileage is also a plus in these days of increasing prices, but again nothing to go nuts over (maximum of 1 more mile to the gallon). Along with an earlier removal of the resonator (or pre-muffler) pipe, the engine is "breathing" easier and sounding better. Although I don't have a dyno to prove anything, I like the sound better and it cost me nothing but some time under the hood.

 

kool, interested in pictures. I find it hard to believe that any modification to the stock box would make any power gains over what Honda has engineered for us with lots of quantitative r & d, sound gains aside however would absolutely love to be proved wrong by some good ol' backyard engineering. but hey nothing against you, im all for if it works for you then why not.

 

This mod will give you 8 more hp with a k&n filter. i know because i did this on a dyno. i also know that if you install a tornado in the air filter, it will give you 5 more hp, dyno tested. if you don't believe me, check out import hot rod garage.com for info. ronald van erkel owns the dyno shop. why pay 2to 3hundred for a cai when you can modd the oem box and get the same results. thats money you can spend on other modds.

 

im thinking of doing this but dont have a dremel. is there any other cheap tool i can use? like a saw

 

I took a small steak knife to my box and some pliers. Luckily, the plastics broke dead flush when I pulled them with the pliers so the removal was very easy.

 

I was also thinking of modifying the oem box just to help it with cold air more than anything. I purchased a K&N air filter already and took off the box cover but the heat soak is VERY annoying!! might try the gutting and cutting technique to help keep the noise. give it slightly colder air and also reduce heat soak!

 

This mod seems very tempting. How do I know if I have heat soak?

 

your car will feel slower

 

I was going to mod my airbox; after an inspiration from the K&N short ram intake; I just bought a Injen intake and i'm in love. No heat soak, gas mileage has gone up substantially; on and VTEC IS HEAVEN!

 

And I thought I was the only person that did it this way ... And yes when I used the pliers it broke flush with the box too!