keep your airbox?

Acoustic tuning air boxes is usually done to quiet down induction noise. In a few rare cases it is done to make the induction noise sound more racy, and occasionally (motorcycles mostly) for a helmholtz resonance tuning effect that boosts a very small segment of the power band. Usually this is tuned for a troughs (dips) in a peaky powerband band with lots of peaks and valleys to smooth things out and make throttle response more managable.
 
I was going to add

The effect is pretty small in terms of power but very noticable on a light bike of a few hundred pounds. Anyway by the time you did enough research, testing and work on one you'd have been better off doing a more effective mod.
 
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I was going to add

The effect is pretty small in terms of power but very noticable on a light bike of a few hundred pounds. Anyway by the time you did enough research, testing and work on one you'd have been better off doing a more effective mod.

I heard that they tuned the air box on bikes, but they keep calling it ram air.. ugh..
 
I would get a cheap Magnahelic gauge off Ebay and run some clear PVC tubing from it to the spot between the headlight and where you want to put the hole.

Are you anticipating a negative pressure zone there? If so.. what about cutting a hole in the fiber glass panel as well?
 
WOW... uninformed much? :roflmao:

take a look under the hood of a prerunner, drag car, mud truck, comp rock buggy... what do you see? probably not a stock airbox... but I'm just guessing. :wave1: :peace:
prerunner, drag car, mud truck, comp rock buggy, Jeep Cherokee.

Which one doesn't fit? I dunno about you, but my Cherokee's engine needs rebuilding a HELL of a lot less than any of those cars does. Their filters don't do as much because they don't need to, because the engines don't last nearly as long. I've seen racecars with wire mesh with bigger holes than a car's grill being used as the only filter medium.
 
Well all this airbox on the right stuff is pretty nifty, but what I really like about it is it leaves room to fab up or use a battery tray from a RH Aussie XJ to mount a 2nd battery!:party:
 
Well all this airbox on the right stuff is pretty nifty, but what I really like about it is it leaves room to fab up or use a battery tray from a RH Aussie XJ to mount a 2nd battery!:party:
 
I know some of you guys advocate removing the airbox and others don't BUT if one were going to what do you think of this kit? It seems to keep most of the OEM airbox design, except it allows more air in.....I think it is a better design and sort of mimics what some of you guys are doing with cutting or drilling stock airboxes?

http://www.autopartswarehouse.com/d...idQQCold_Air_IntakeQQ19912001QQA86310136.html
 
I don't like that airraid kit for several reasons. 1) it doesn't eliminate the corugated rubber tube, 2) for what you are getting you are paying too much, and 3) same sealing to thehood as the rest of the kits.. poor seal.

I purchased a S&B CAI kit for $100 new on ebay. It has its own air box which is only open to the front, which I will be sealing better to the outside air.

BTW, nice sig.. I like this one better though "And though I can hide my cold gaze, and you can shake my hand and feel flesh gripping yours and maybe you can even sense our lifestyles are probably comparable... I simply am not there. "
 
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I don't like that airraid kit for several reasons. 1) it doesn't eliminate the corugated rubber tube, 2) for what you are getting you are paying too much, and 3) same sealing to thehood as the rest of the kits.. poor seal.

I purchased a S&B CAI kit for $100 new on ebay. It has its own air box which is only open to the front, which I will be sealing better to the outside air.

BTW, nice sig.. I like this one better though "And though I can hide my cold gaze, and you can shake my hand and feel flesh gripping yours and maybe you can even sense our lifestyles are probably comparable... I simply am not there. "

Thanks, will take note of the S&B kit. Thanks for the remark on the sig.....yeah I like that one as well.........LOVE that movie, Christian Bale is the shit, he should have got an award for that movie......very under appreciated actor if you ask me.
 
You wouldn't catch me hacking up the air cleaner on an Infinity G35 or a 09 Camaro, but the XJ? I doubt they had performance in mind when they threw the box in these things.


They're designed to be quiet, fit in the application, be cheap to make, and cheap to install. Not to mention help keep the EPA happy with the cafe standards. Honda and other motorcycle makers do the tuned airboxes, but even they're facing government restrictions, so complying comes first, then producing a good product.:soapbox: <insert my rant here about the EPA making autos more complicated and less reliable (regs killed any hopes for a US market JK diesel, and check out the current diesel trucks if you don't believe me on complexity), and making it expensive for automakers to do business.


I took a dremel to my airbox... from the top of the stock hole I went around to the 'fender' side and back... did the same on the bottom, and connected the two with a diagonal cut along where the airbox 'cuts in' for fender room.
 
You would probably get better results from getting rid of the corrugated tube and replace it with smooth. I seem to remember reading that a corrugated tube has the effective air flow of a tube = to depth of corrugation - ID what I'm trying to say measure the depth of the corrugation subtract that from your smallest ID thats the effective diameter. I might be wrong on this it's happened once before
 
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