My K&N panel filter arrived today and I am ready to hack the airbox. I have read other threads that say cut up the passenger side up to the mounts, but should I make 2" holes, or just cut a big one? What's your best advice here.

 

Wish I had a photo ...


I'll try ASCII ....

Excuse the DOT place holders -- make believe they are spaces !!!

................Passenger side...............Wheel Side

......................................Bottom View

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|.....+.............................+....|........ ...............................|
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|..........................................|...... .................................|
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Drill 1/4" holes at crosses, connect the holes with a
sabre saw ... leaving one HUGE hole that can also
be later connected to a RAM air setup if you leave enough
lip around to bolt on the flange.

The above setup and the K&N got me 13.51 @103 mph ...
and considerably louder S/C whine ....

 

Yes - one BIG hole. I didn't really see much of a difference in ET or speed with it.

 

John,

Click on the link and scroll down.
Airbox Mod

 

Thank you all for the explanation, suggestion, and pics.

 

here is what I did, I am including links not pics to save bandwidth.

https://www.f150online.com/galleries...38-34-9726.jpg

https://www.f150online.com/galleries...38-34-9727.jpg

https://www.f150online.com/galleries...38-34-9725.jpg

 

Quit mutilating your stock airbox and go this route guys/gals:

http://lightningforums.com/forums/sh...hp?threadid=54

 

I tried this, but chickened out because it seemed like gravity would cause the filter seal at the middle to be less effective. Yessir, it's Dremel time for the Juan-Man.

 

Well, it doesn't and couldn't because of the rigidity of the filter, BUT, you can fix this by cutting 2 slits in the middle of the airbox and using the zip ties "heads" at the top of the slits.

Understand? You stick the zip tie through the slit, the head of the zip tie will sit flush against the airbox, then take the loose end under and around filter and insert through the other slit on the other side, then slip a 2nd zip tie head down over the loose end, and cinch it down snugly. Clip excess for a flush look.

VIOLA! Your problem is solved. You can also do this on the 2 ends of the box too, instead of wrapping zip ties all the way around it like in the pic. Makes it look less of like a mod (i.e. you hardly see anything but the zip tie heads when looking down onto the box).

silverzz28 has already done this and it works great! I'll try and get some pix scanned of "version 2.0" of this mod in the next day or two

 

I just have one big hole, On the left of the airbox.

 

Well, I Dremeled my airbox as in LTNBOLT's pics, and pulled out the fenderwell hose also. Basically, there are now three huge holes in the airbox.

BfB's mod looks good, but I got an itch to cut plastic that just had to be scratched. :o

During a post-modification midnight grocery run this evening, the Grossly Inaccurate Factory Boost Gauge now passes well beyond '10,' whereas it never quite got to 9, so it looks like I might have picked up a pound or two of boost according to the BS meter in the dash.

I must confess the poser in me likes the very loud whine more than anything else. I'll have to strap on the G-Tech this weekend and see if the numbers change at all. I'm guessing I've probably added 5 or 6 RWHP, but that remains to be tested. Not bad for a free mod, I guess...

I'll be fabricating a flanged-duct type thing to work with my Cervini's hood. Water management is an issue there. I'll keep you guys posted.