Drilled Airbox

[k1ckb0x3r]

Can someone please post some picks or draw some in photoshop of where you are drilling the holes in the airbox?

 

[J91FORD]

do you drill these holes on both sides of the air box?

 

[GJarrett]

Howdy!

Man, you're putting way too much thought and planning into this. If you're gonna do it, just remove the box and start drilling away like crazy. Mine looks like swiss cheese that's been used for skeet practice. There is no "correct" placement of holes (as long as you stay below the filter).

Gerald

 

[k1ckb0x3r]

I'm just worried about it sucking in hot air which would hurt it more than help it.

 

[Big Poppa]

I drilled the holes all the way around (all four sides) the bottom half of the box. To date, Ihave done this to my explorer, Bronce, and Ranger. All had good porwer improvements and much better sound under acceleration.

Swiss cheese thats been used for skeet practice- nice analogy.
Good Luck

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'91 2 dr Eddie Bauer
modified air box
K&N filter
MUCH MORE TO COME

 

[PunkChild]

What type of airbox do you have? Is it the box that uses a rectangle filter or the one that uses the cone filter?

 

[Big Poppa]

Rectangle

------------------
'91 2 dr Eddie Bauer
modified air box
K&N filter
MUCH MORE TO COME

 

[Nonoy]

If you are worried about the air box sucking in hot air, use a flex tubes. You can get it from Sears of different types/size. Decide what size you want and buy the the same size to make a holes. I used the 3/4" flex tubes and just insert it into the holes in the box and run it to the back of the headlight. Some posting they use the flex tubes for vaccum cleaner and run it down the bumber air dam. You can use plastic ties to hold the tubes in place. Good luck

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NY State of Mind

 

[TymeKeeper]

I'm gunna have to try out that "Swiss Cheese used for skeet practice" idea Dead Link Removed what size, or does it matter Dead Link Removed



------------------
Jim
'92 Eddie Bauer Explorer
Dual 2.25 exhaust, no Mufflers
Cobra 148GTL W/K40 Mag
235/60's
My Baby!!

 

[Trckmagik]

Just make sure you are only drilling on the bottom half of the airbox. "And yes" People have actually drilled on top and bottom! Dont!

------------------
Brian Green
-2001 Sport Trac
-1992 Explorer 2wd w/ six
inch suspension lift
-1992 Ranger 2wd w/ 5.5
inch suspension lift
Trckmagik@aol.com

 

[S.Matsushige]

I originally had two and a half inch holes cut out on all four sides and a couple on the bottom. I recently increased the opened area by using a hacksaw and cut the majority of the walls out leaving just the top lip and the four corners and the original air duct. I then took some fiberglass screen and epoxied it over the openings to keep large objects from entering the box. Works great. I got the screen idea from a member.

 

[A91EBexplorer4x4]

S.Matsushige,

did you notice any difference from the
2 1/2" holes to the all open air bos but corners with the screen? just wondering if you saw an improvement or not and was it louder? thanks, later

 

[Mr.Mike]

Is there any chance that a drilled air box could contribute to an O2 sensor going bad or the check engine light coming on? I have a drilled box with a K&N filtercharger on my 91. I ran it that way through fall and winter, then my check engine light came on, and my code scanner indicated a bad O2 sensor. It may be just coincidence.

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91EB4X4;2.5^+31"BFG/TAko
custm-cat-back;etc.131+mi
00 Subaru Forester (nice)
\__o
______\_,)____
--------\--------

 

[KSolo]

Just curious....which is better, drilling the airbox or spending a few $$$ to go with the KKM?

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1999 Limited
no mods yet...but considering

 

[jimiday]

I have the cone type air filter. I took out the bottom part of the box and drilled 18 1" holes, 6 vertical lines of three holes each. This actually eliminates most of the airbox while leaving a sufficient frame and not allowing objects to be sucked into the box. Additionally, I think adding more smaller diameter holes has a better sound than fewer larger holes. I'm sure there are lots of opinions on this, but this worked for me. I added a K&N drop in filter and Bosch Platinum +4's at the same time and got a nice performance boost for the buck and actually increased my mileage by 1.5 mpg. Good luck!

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1996 Explorer Sport 4x4
4.0L OHV w/auto & 4.10's

jimiday@aol.com

 

[S.Matsushige]

A91EBexplorer-Sorry to get back so late. I was out of town for a couple of days. About the sreened airbox with larger openings, I hadn't noticed any increase in sound (maybe due to the screens), but there is a slight increase in throttle response and accleeration. It maybe that the amount of holes and the size were sufficient so the noticable difference might be minimal, but for the person who hasn't done it yet would definitly notice a big difference in both throttle response and power. How's gas prices where you are? We're at about $1.70-$1.75 for regular unleaded here in Honolulu. The neighbor islands have prices as high as $2.30 a gallon for regular. YIKES! Hopefully, the larger openings in the airbox and my slower freeway speeds will increase my mpg.
Mr.Mike-I've seen people getting O2 sensor reading when actually it was their fuel pressure regulator. I've had the holes in my airbox for sometime now on my '91XLT, but still have the original O2 sensor. My FPR went about a year ago and I replaced it.
KSolo-Figure in the cost of drilling holes-no cost. K&N drop in filter-$50. I think the gains you'll realize for such an easy and low cost modification is worth it.

 

[TymeKeeper]

I drilled a bunch of holes in my air box, and noticed that my oil pressure went up a bit, along with the extra umph! Dead Link Removed Works to me.. Now I need to figure out what to do next, I am thinking about putting in a chip, but not too sure about which one to use, any idea's?



------------------
Jim
'92 Eddie Bauer Explorer
Dual 2.25 exhaust, no Mufflers
Drilled AirBox
Cobra 148GTL W/K40 Mag
235/60's
My Baby!!

 

[RonN]

Has anyone put a sensitive vacuum gauge on the air cleaner box and measured the restriction? Or is everyone just guessing.

Ron N.

 

[SCOTTC]

about a year ago i took my filter box out and "redesigned" it by cutting out all sides with a jig saw leaving nothing but the corners. i then took 1/2" mesh and caulked it to the inside surface of all the sides i had cut out. leaving a box that looks more like a bird cage. I DONT NEED A SENSITIVE VACCUUM GUAGE to know it made one HUGE improvement. also live in tucson, az. the heat doesnt affect it that much down here, so i dont think you have alot to worry about. try it,if you dont like it buy another box from the junk yard and go back to stock! just my .02 worth

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SCOTTC
93XLT 4X4 4DR.
bosch plat.4s
jacob wires
k&n kit
mod. airbox.
skid plate
maxflow exhaust
more to come!

 

[S.Matsushige]

From one Scott to another, thanks for the screened box idea. I knew I read it, but wasn't sure who posted it. The slight improvement in throttle response and acceleration is worth the extra time to go back in and re-do the box. Adding the screen was the part that made me want to increase the openings. Works great! Thanks again for the idea ScottC.