DIY: High Flow Stock Airbox (Swiss Cheese Mod)

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highrollin113

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well i have a k&n drop in too, but ya im noticing a big difference, i really can not describe how shocked i was when i went for my first test drive i punched it and it sounded throatier and had so much more go when i need it, plus when i need it at around the 65m/hr range it was lagging before now she has jam i absolutely love it, and no it will not screw anything up at all in fact it isnt even perminent if you dont like it you can screw something solid over the cut out in the airbox and its done. but trust me you will love it, i did notice it was idling higher for about 80km but i think the computer has adjusted for it now

my kon and your hoe are like twins except i havent derailed completely or demolded but same colour and rims, so what im trying to say is you have great taste haha
 
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chip

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I'm sure this mod will absolutely set off a K&N drop in!

That's what I'm gonna do!
 
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ypsetihw

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cleaning the MAF is super easy . . . just take the band clamps off and unhook the harness. just look at it, usually if you touch the screen you'll see a big smudge of crap come off on your finger . . . that's when you know its time to clean it.

go get yourself some CRC MAF cleaner for like $7 at your auto store, spray the crap out of it, it dries instantly. put it back on and voila!

---------- Post added at 05:18 PM ---------- Previous post was at 05:16 PM ----------

would this mess up the hoe or kon at all ? are you seeing big gains highrollin? i might want to do this but needs some answers first

totally safe for basically any car as long as you only cut up the DIRTY side of the box. not gonna see big gains on the dyno, but you will see some throttle response and it won't bog as much on the highway. plus you'll get a little more sound out of it. you'll see the most out of it if you use a k&n drop-in at the same time.

highrollin113 - love the mesh screen and vent to the fender well! good thinking!
 

clean454

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highrolln if u put the screen on the bottom of the box..

can u put the box back in without the bottom plate?

or does that box mount to the plate?

just a idea
 

jomulk56

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Clean I'm pretty sure you need that bottom plate to attach the stock air box. It's got 2 holes where the box "snaps" in.
 

highrollin113

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the screen is on the bottom of the air box and well it does mount to the plate, but because i couldnt cut through the plate with a cutting disc on my grinder i asked my neighbour (a welder) to cut with a torch, so that took a day so i did drive for a day with the airbox just loose and it was fine its so tight in there that its not going to go anywhere so you could probably get away with it if you dont mind it flopping around in there a bit, i never heard it rattling around either but i would recommend mounting it properly
 
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Redhoe01

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yp and highrollin, awesome info. Doing this next weekend. I have a K@N drop in as well and cant wait to see if it picks up better. I bet if you use a dremel or something and smooth out around the cut edges, it will flow that much better. A small scale port and polish type thing.
 

Thumper8302

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i just did this a couple of hours ago since i finally found my damn drill in moms garage lol... just a reg filter but i did hear and feel an improvement..... i didnt do the large holes but i honeycombed the hell out of the dirty side with a 9/16 bit....
 

highrollin113

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so i am thinking about getting a larger diameter pvc pipe than the hole and angling it and fastening it to run from the hole in the steel down and having the bottom angled so it will force air up, soes anyone think this will help? also there is a gap between the plate and the airbox so i would seal that somehow too
 
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ypsetihw

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so i am thinking about getting a larger diameter pvc pipe than the hole and angling it and fastening it to run from the hole in the steel down and having the bottom angled so it will force air up, soes anyone think this will help? also there is a gap between the plate and the airbox so i would seal that somehow too

*this is just my opinion not science*

once you open up the stock airbox, it has plenty of flow to keep up with a stock tune. if you have a custom tune like blackbear or something, chances are you will see a bigger gain from a more wide-open intake, but it is equal chance that you already have a custom built or aftermarket CAI or some other open-filter-element design, so it prolly isn't an issue.

as such, putting some sort of forced induction "snorkel" on the intake prolly isn't gonna help you any, because after you vent the airbox, the restriction then lies in the stock, pre-TB baffling. even if a snorkel helped, you'd prolly need an engine tune to take advantage of it, and opening up and smoothing the baffling between the MAF and TB would give you a much greater benefit than putting a ram-air setup in front of the filter.

in other words - I stick by my statement that this mod is specifically for those people who want/have a high flow stock filter on a stock tune, and want to open up the stock intake without major re-design.

just my $.02 :beer:
 

Stockfornow

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Works great for a stock car! I have done it a couple times on my B Bodies. (See sewer pipe/swiss cheese in sig ;)

4410903911_42850ace21_b.jpg
 

DenaliAK

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I'm not asking to rain on anybody's parade or anything, but because I am seriously considering doing this and don't know the answer to the following question:

What happens if water gets "splashed" in there somehow and sucked down the intake?

I live in a fairly wet, and sometimes very wet, place...rain, puddles, slush, condensation, snow, ice, spray...you name it, we got it...and I'd hate to kill something on the engine by getting some water splashed up in there.
 
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ypsetihw

ypsetihw

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What happens if water gets "splashed" in there somehow and sucked down the intake?

I live in a fairly wet, and sometimes very wet, place...rain, puddles, slush, condensation, snow, ice, spray...you name it, we got it...and I'd hate to kill something on the engine by getting some water splashed up in there.

valid question - water in your engine could potentially cause it to stall or even hydrolock, but you'd have to suck up TONS of it all at once, basically by submerging the intake in a bucket at high RPMs. think about it - when you use seafoam, you suck liquid into the engine. when you add water/meth injection, you purposefully SPRAY water into the engine. not to mention, your engine compartment isn't air or water tight, and stuff is getting "splashed up in there" on a regular basis.

lets make this clear - YOUR STOCK INTAKE SETUP ALREADY HAS HOLES THAT LEAD TO THE OUTSIDE WORLD, THAT'S HOW AIR GETS IN THERE IN THE FIRST PLACE . . . THERE IS PROBABLY ALREADY DEBRIS IN THERE, AND ITS NO BIG DEAL, THAT'S WHAT THE AIR FILTER IS FOR . . . ok now that you've digested that for a minute you can relax.

keep in mind that the holes (both the stock inlets and any that you might add) are on the DIRTY side of the airbox, and the air filter is still in the way, not to mention that the airbox is still in the same position, so there is no risk of the filter element being submerged like you might have with a cold air intake that sits down in the fender.

in any case, a little "splash" of water isn't gonna get anything wet that wouldn't already . . . now if you go cutting the entire bottom out of the box like highrollin did, then you should at least put some mesh in there. but still . . .
 

highrollin113

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to add to the that i too live in a snowy fairly wet place as well and we had rain snow for the last week(my sig pic was taken last week sadly enough) and i never had any problems, before i cut the steel plate i looked at the underside of it and it was fairly clean no real signs of weathering water getting up there, but like yp said its the dirty side of the box thats where the air goes anyway and if there is moisture in the air some will get in and our engines run hot enough that when a small amount gets through it will boil off and evapourate anyway
 

DenaliAK

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Alright, roger that, guys.

For some reason when I picture this in my head the holes are directly exposed to the intake with the filter above them. Hmmm.

Anyway, I appreciate the info. And no, I don't plan on submerging my Denali....so I probably won't worry about it.

I may go pick up a K&N drop-in today.
 

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