D.I.Y. Modding Airbox

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Hayes90
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D.I.Y. Modding Airbox

Postby Hayes90 » Mon Aug 24, 2009 12:42 pm

This is a cheap and easy way to get the same or verrry close to the same performance as a CAI would give you... and it costs nothing!

DISCLAIMER: This is what I did on my vehicle and had great results with it. However, I am not liable if anything happens to your car because of this.

The airbox/intake modification:

You are almost definitely losing power with a cone filter, instead of the airbox in place, because of all the hot air that the cone filter is exposed to. Cone filters work on either a cold air intake or when being used with a heat shield. To further prove to you the power loss of a cone filter in place of an airbox, here is a dyno test from Techtonics Tuning of an open-element conical filter versus an airbox. There is quite a drastic loss in power with the conical filter. http://www.techtonicstuning.co...7.JPG

First, buy a high-flow drop-in air filter of your choice.

What I did, and what many others do, is modify the stock airbox. All you really need is a dremel, or maybe a utility knife, if that may work

Next, is cutting out part of the front/fender side of the airbox. I used a ruler and straight blade to slightly draw out where I wanted to cut exactly. I used many of the airbox’s lines to cut the cleanest looking cut. Some people swiss cheese the airbox, which in my opinion, is not the best method to go about this. You can just cut a whole clean piece out of the airbox. It will allow more air and look much more professional and clean. You honestly can't tell the airbox is modified if you do it in this manner.

Here are my pictures;















Woo!!


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Qxxx4
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Re: D.I.Y. Modding Airbox (Hayes90)

Postby Qxxx4 » Mon Aug 24, 2009 2:59 pm

wont the air filter get much dirtier therefore getting clogged sooner?

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miamiheat3332
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Re: D.I.Y. Modding Airbox (Qxxx4)

Postby miamiheat3332 » Mon Aug 24, 2009 3:34 pm

i personally think the mod i posted does more than this but, eh i didnt try this either, but i know and other people have said you notice gains if you do it by cutting into that other box below like i did.

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Hayes90
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Re: D.I.Y. Modding Airbox (Qxxx4)

Postby Hayes90 » Mon Aug 24, 2009 7:14 pm

Qxxx4 wrote:wont the air filter get much dirtier therefore getting clogged sooner?
http://www.knfilters.com/filtercharger.htm

volp
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Re: D.I.Y. Modding Airbox (Hayes90)

Postby volp » Tue Aug 25, 2009 5:33 am

correct me if i'm wrong, but aren't you still going to be sucking up hot air from the engine compartment if you chop up the airbox? cutting a hole on one of the sides and running some tubing to the grille to let in fresh air would be better, no?

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miamiheat3332
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Re: D.I.Y. Modding Airbox (volp)

Postby miamiheat3332 » Tue Aug 25, 2009 6:47 am

yeah volp's right, same thing i was thinking when i posted.

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Hayes90
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Re: D.I.Y. Modding Airbox (miamiheat3332)

Postby Hayes90 » Tue Aug 25, 2009 1:36 pm

thats why you cut it opposite of the engine, because there is a hole in the fender right next to the hole in the box, letting in cold air

volp
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Re: D.I.Y. Modding Airbox (Hayes90)

Postby volp » Tue Aug 25, 2009 1:53 pm

maybe but i still vote for the tube because it'll be forced in while your driving as opposed to just being sucked in by the engine

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Hayes90
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Re: D.I.Y. Modding Airbox (volp)

Postby Hayes90 » Tue Aug 25, 2009 2:18 pm

ill be coming up with a good idea, dont worry

VG33QX4
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Re: D.I.Y. Modding Airbox

Postby VG33QX4 » Wed Nov 17, 2010 1:53 pm

when doing this on vg33 equipped vehicles it is very important to relocate the INTAKE air temp sensor.

i did this by elongating the wires, cut a corresponding size hole in the side of the box and insert the sensor.

the iat sensor on models with vg33 are located behind the fog light in the resonator tube, it is easily removed by forcefully pulling it out. use the grommet that is on the snorkel tube for your box.

difference in air temp readings from these two locations is about 20 degrees, this is significant when it comes to ignition timing. i noticed slight knock prior to moving the sensor. after it was completely resolved

r81gsr95
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Re: D.I.Y. Modding Airbox

Postby r81gsr95 » Sun Jun 23, 2013 11:22 am

I wanted to bring this thread back from the dead to ask a few questions. Anyone else do this and notice a difference? It would seem that if you cut the box open then air will not longer be drawn from the hole which draws cold air from behind the front bumper. So instead it sucks air from the engine compartment. I'm sure that this mod will allow for more air to be drawn into the engine, but i think it will be more warm air.

So is there any gas mileage improvement? And any power improvement? Thanks

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Chris.m
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Re: D.I.Y. Modding Airbox

Postby Chris.m » Sun Jun 23, 2013 9:50 pm

Honestly, the only real difference is a louder intake sound.

Other than that, you may trick yourself into thinking that it has better throttle response, and more power, but since no one has done a dyno comparing before/after, we will never know for sure.

That being said, I've left my resonator off :biggrin:

Josh G.
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Re: D.I.Y. Modding Airbox

Postby Josh G. » Tue Mar 10, 2015 1:25 am

Would this affect smog check in CA in any way? Or would the station just tell you they couldn't do it?

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rgk
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Re: D.I.Y. Modding Airbox

Postby rgk » Tue Mar 10, 2015 4:58 am

There's a good reason why the airbox front hose resides at the grille. Your filter is toast with this method as soon as you develop an exhaust leak.


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