Drilling Holes in Airbox????

[RJXplorer]

i have a '94 XLT with a K&N and was thinking about drilling out my airbox to improve airflow.....I was wondering if this would be a good idea, or if sucking in hot engine air would not help me at all.....any advice on whether or not this is a good idea or if there are any other drawbacks would be much appreciated!!

----<RJXplorer>----

 

[S.Matsushige]

RJ-I think one of the main advantages of drilling the hole would be to free up the restrictive airbox. Much like the KKM or the K&N conical filters without having to spend the $100. As for the engine sucking in hot air, ultimately you would want the coolest air possible which could be done by constructing a ram air inlet. There are a few members that have gone this route. I feel the drawback to this is the chance of drawing water into the engine. I have gone the holes in the airbox route on my '91 since I had the dropin K&N with a spare. I believe that since I do more highway driving, the air under my hood isn't as hot as if I were standing still. Now if you are you were doing some rock crawling it might be a different story. This is just my opinion and hopefully someone else could give you other reasons to do it or why not to do it. Hope this helps.

 

[Gigantor]

On my 93 4dr I installed an K&N with a modifyed air box. I noticed a HUGE improvement in power, however I did not notice ANY improvement in MPG. I think findings will greatly varry because of setups...gears, tires, driving conditions...
Thats just my knowledge, I hope it helps you make your decesion,

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Nick
'93 XLT 4 Door 4x4

 

[Tino]

Drilling holes is always a good idea with a drop in K&N air filter. At first i did not drill holes but when I did, I noticed a lot of improvement even gas millage. I drilled holes in a different way. I bought a 1" hole drill to fit a 3/4" Sprinkler pipe (PVC) . I drilled two holes in front besides the original holes and and used the T connector i got from the sprinkler section of Home Depot. I also added 2 holes at the side using a 3/4 Swivel lok multi position liquid tight coonector (a corrosion resistant nylon) also from Home Depot plumbing section. With this connector, you can attached the PVC pipe at a calculated length then by just tightening the lock nut wil hold the PVC pipes. The other end is lock nut with O ring to hold it in place to the box. I angled it going to the front. I also plced an aluminum screen to prevent leaves or insects from getting in. I cut the screen from an old oven Hood filter. To hold the screen in place I use a plstic ties. I wrapped the pipes with a self stick duct insulation foam with aluminum foil to protect and keep it cool. Another holes on the side using a T connector for the sprinkler. You can plan it more where you want to drill holes. Make sure the hole where you have to place the connector is not too high to touch the air filter. Before I forgot, I wrapped the box with the selt stick insulation aluminum foil before making holes. The insulation will keep the air cold and as well as decreased air noise. I got everything from home depot! Good luck!

Tino
1997 XLT V6 SOH Black

 

[CBoug76]

Photo's Tino, Photo's!

Please!

 

[Blaine Cooper]

Yes, photos please.

 

[Tino]

I already took the pictures all I have to do is have it develop. Just wait.

Tino

 

[RJXplorer]

WOW---First....I would liek to say...darn good work Tino...pictures would help greatly.....my only question is, where in the hell do you link the pvc pipe to the outside??....i know you aren't driilin' hole in the fender....so where is the cold outside air comin from??

TY!!!!

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RJXplorer
'94 XLT - 30" BFG AT's
"King of Power Slides!!

 

[Tino]

From the side air box (engine side) I run a 3 PVC pipes originating from 3 holes going towards the back of the Head light. I wrapped the pipes with a self stick aluminum faced insulation. There are several holes at the back of the head light that you can decide to divert the pipes to sucks air. You can also cut holes into the plastic/rubber mat/coverings by the grill near the head light but do not connect it to the pipes coming from the box to avoid water from coming in. The purpose of this is to supply more air. I'm trying to find a screen that angle in a way to divert water. but for the mean time a hole I think is sufficient.

Tino

 

[RJXplorer]

Tino -
I see one large problem with your instructions, while I appreciate your help, they cannot help me all that much, as you have a '97 Explorer, and I have a '94, and the airboxes are completely different!!
Your tips should apply a little, but as to the exit areea, I believe that your airbox is on the opposite side as mine. However your info on the drilling of the holes was very informative, and i plan to do that tthis weekend when i replace my fuel pressure regulator, as on my trip from KC to St. Louis today i got a maximum of 12 mpg!!!!
Thanks for the tips!!

 

[Tino]

Now I got a problem. The picture did not come out right. I'll try again. Today I bought an extra K&N filter. From this web page I remember reading "its a good idea to have a repcement ready" specially during winter time. I have my old one on the process of drying after cleaning it with tap water I'll spray it with the K&N oil that comes with the cleaning kit. While replacing the filter, I saw more possibilities to add more holes. More holes = more air! although the additional holes is now sucking air from the engine compartment which I think will not matter much. With Flowmaster muffler and K&N air filter is a magnificent HP.

Tino
1997 XLT, V6 4.0 SOH Controltract

 

[Tino]

If anybody can install a flex pipe from the air box will be better. You can flex it to werever holes you want air. I saw one in Sears but it cost too much.

Tino -(again)

 

[RJXplorer]

Ok i finally got the ballz and the toolz to drill the holes, WOW wat an imporvement, now all i have to do is figure out how to install my new fuel pressure regulator, i have the chilton, but it isn't exactly an easy part to ge to, but thanks for all the tips!!

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RJXplorer
'94 XLT - 30" BFG AT's
"King of Power Slides!!"