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Drilling holes under air box

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Old 03-31-2010, 08:07 PM
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Default Drilling holes under air box

Hey all! Do you think If I was to make more holes in the area of where the stock airbox was, I'd get better airflow. Or maybe cut out a lot of that area?
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Old 03-31-2010, 08:11 PM
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Default Hot Air

You need a shield between the engine and the air filter, these actually get more hot air than the original air box.
Old 03-31-2010, 08:13 PM
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Buy a heat shield.

Or make one from sheet metal/thick plexi/etc.

Trick is to keep the hot exhaust gasses from entering the IAT or CAI.
Old 03-31-2010, 08:14 PM
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don't drill the holes, the first rainy day or mud/water hole you hit, you will be sorry.
Old 03-31-2010, 08:14 PM
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yeah im going to picking up some sheet metal and making one soon. But you think I should still open up that area some what?
thnx!
Old 03-31-2010, 08:16 PM
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yeah maybe water being splashed up wouldnt be so good. Ill make the heat shield and leave the body alone. thanx all!
Old 03-31-2010, 08:20 PM
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Yea. Your not gonna be able to build a ram air by drilling holes.

and the intake doesn't suck in enough air to cause a pressure drop in that area.

Just keep that hot air out!
Old 03-31-2010, 09:02 PM
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you need to swap out that Intake manifold for a 99+ if your looking for gains......
Old 03-31-2010, 09:06 PM
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Originally Posted by 98_CherokeeSport
yeah im going to picking up some sheet metal and making one soon. But you think I should still open up that area some what?
thnx!
of course,, open it up with a snorkel.
Old 03-31-2010, 09:23 PM
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Originally Posted by 98 JeepJeep
you need to swap out that Intake manifold for a 99+ if your looking for gains......
They LOST 5hp on their '98 XJ at jpmagazine.

http://www.jpmagazine.com/techarticl...ies/index.html
Old 03-31-2010, 09:35 PM
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Any sheet metal or metal tube in or close to the air intake will become a heat sink which absorbs heat which raises the intake air temp. Not good for performance and main reason the factory unit is all plastic - less heat transferred to the intake air.
Old 03-31-2010, 10:08 PM
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Originally Posted by djb383
They LOST 5hp on their '98 XJ at jpmagazine.

http://www.jpmagazine.com/techarticl...ies/index.html

I think you might want to read that again...
Old 03-31-2010, 10:14 PM
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Correct CAI goes thru the fender well... if there is one. If you have it in the engine compartment, you'll get nothing but HOT air.
Old 03-31-2010, 10:16 PM
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i'll tell ya though that home-brew looks awesome.
Old 04-01-2010, 05:41 AM
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Might want to consider cutting some of the metal away that is between the headlight and the radiator. Going from the edge closest to the rad you can cut maybe 1.5" or more of metal away to open up the front a little bit. If you don't go bumper deep in water/mud, the plastic surrounding the headlight provides a good bit of splash protection.
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