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Discussion Starter #1 (Edited)
I was considering the TRD intake but for the price I just wasnt sure it would yield that much benefit. So I decided to start looking to see if there was any improvement to be had with the stock intake system.

At first thought, looking at the intake tube, I thought there would be lots of room for improvement. I mean really, what's this elephant seal nose looking thing doing on the intake tube? Turns out, that upon closer inspection (IMO) this was not designed for sound but to act as an "air reserve" for the stupidly designed air box. The intake, as designed with those "lobes" actually should not cause much disturbance/restriction in air flow going into the engine. The real restriction comes from the 2.5" inlet into the stock air box.

It seems that in order to add a particle dump on the air box, Toyota necked down the inlet to the box to 2.5" by sleeving a 2.5" by 2" tube into the 3" molded inlet, then on top of that added a factory "Tornnado" air vortexer thingy. Creating a trap for large light stuff that could have been sucked into the intake. All of this is the largest contrinutor to intake restriction (IMO).

The stock TB is 3" in diameter, so how is a 3" throttle body supposed to get enough air when demand arrises, (smashing on the throttle to pass for example) if it's only fed by a 2.5" inlet? Well it really can't so (IMO) Toyota added the extra "air reserve" lobes to the intake to help. Unfortunately I don't really think those hold enough air in reserve to matter and thus we (2010, 2011) guys are stuck with a somewhat anemic truck.

So what is one to do? Well if your me I could care less about the large particle dump because I have an air filter to do that (infact there is an additional filter in the upper air box lid so you really have 2 air filters), so I cut the small sleeve out and removed the "tornado" wanna be vortexer, getting rid of the restriction. I didn't bother replacing the intake tube at this point cause like I mentioned above I dont think it's that much of a restriction.

Does the tuck perform better? Well thats going to be tough for me to say honestly cause the same day I did this, I added my Demello sliders effectively adding an additional 70lbs to the truck, which I think pretty much absorbed the any power increase I would normally have felt. IMO it does feel a little more responsive and I think if there would not have been a weight gain in between before and after, the truck would have felt much more improved.

So, on with the pics to show you what I'm talking about.



Looking into the stock air box with the filter removed you'll see the tiny 2.5" inlet.


Lookig at the outside of the inlet you'll see that it's really a much larger diameter but clogged with the wanna be "Tornado"


The "Tornado" is held in place by a removable clip on piece. Once you pop that guard off you can see the "vortexer" is just slid in, then held in by two little plastic welds. I split these with a pocket knife and removed the vortexer.


With the vortexer out you can see the small sleeved piece.


To get his out I used a hole saw about 2.75" or so and drilled it out from inside the box. Then cleaned up any of the remaining material.




Then reassembled with the piece that held the vorexter in (sans vortexer of course) and reassembled. With a K&N drop-in. :D

Love to hear everybody's thoughts.
 

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Laminar (straight) flow is actually better than the Vortex Tornado thingy (turbulent) flow that is caused by this "device" and the internal step that you removed. Basically, the straighter the better!

Most aftermarket intakes are just large diameter, straight as possbile, tubing w/ a less restrictive air filter. Remove the unnecessary blockage(s), change the filter and it's the same principle for a lot less $.

In my 6.0L Chevy LS2 I removed the mass air flow screen and cut off the probe tubing extension that extended halfway across the interior of the air intake tubing. Vroom!


Good job! Let 'er breathe ;)
 

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Do the new intakes completely remove the cyclone pre-filter, or is that vane it?
 

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Good Post,

When my FJC turns. I will VBOX test it stock then perform this mod, along with logging the Air Fuel Ratio and the power out put at the wheels over the test increment (will do 0-100kmh test).

Look forward to quantifying this, I'll post back in this thread as well.

:rocker:
 

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Discussion Starter #8
Do the new intakes completely remove the cyclone pre-filter, or is that vane it?
I think the part he removed was the cyclone pre-filter.
Yeah not sure what your refering to by "new intakes" because there are no "new" parts involved here. Just removed a feature in the OEM design.
 

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Yeah not sure what your refering to by "new intakes" because there are no "new" parts involved here. Just removed a feature in the OEM design.
The intake in the 2010-2011 is a new design from the 2007-2009, hence, new. :)

 

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I can't speak for the air intake on the 2010-11's but that centrifugal pre-filter removes an amazing amount of sand from intake air stream on my '07.

DEWFPO
 

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I can't speak for the air intake on the 2010-11's but that centrifugal pre-filter removes an amazing amount of sand from intake air stream on my '07.

DEWFPO
Ditto. You just removed one of the features that helps make the FJ Cruiser an extraordinary off-road machine - the cyclonic pre-filter. So, while you might have helped airflow slightly (and I had zero fuel mileage drop when I added the Cyclonic Pre-filter to my 2007), you have removed a device that allows the FJ to spent more time in the sand and dust without clogging the air filter...

For the street, possibly a slight acceleration benefit. For the trail, a definite loss of efficiency, IMO...
 

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Discussion Starter #12
I'm aware of the benefits of cyclonic filters and have always noticed that they are only as useful when they are cleaned. Seeing as how the capacity of this one is a cubic inch or two max, I heavily doubt it's effectiveness.

Additionally this mod was intended for those considering an after market intake, where they would be replacing the stock air box anyway. I wonder how many aftermarket FJ intake systems out there (TRD included) would be keeping (or include) this feature and still improve performance?
 

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Isn't the 2010+ intake based on the TRD intake box sans the conical filter element?
 

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Isn't the 2010+ intake based on the TRD intake box sans the conical filter element?
The air box shape is similar, with the exception of a flat filter on the new stock design and the cone shaped older TRD design. The air also pulls from the lid not the side of the box.

Also, on the new stock design it uses chambers/resonators where as the TRD is a straight intake tube.
 

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Yeah I hate losing the helmholtz resonators when upgrading intakes. Notice a bit of loss on the low end and some gains up high in the revs. IMO sounds better though...
 

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Discussion Starter #19 (Edited)
So I'm considering doing this on my 10' now that I bought an are drop in. I'm wondering what the effects of this mod in addition to this other mod would be? Anyone ever try it?

http://www.fjcruiserforums.com/forums/1789082-post66.html
If you take the intake tube off, and look and feel the inside you'll be able to see/feel for yourself that design doesn't interfere with the flow of air into the engine. The device is for sound suppression, removing it will likely not do anything to improve performance. But it will cost you a few pennies in buying plugs for the holes and extending the vacuum line off the fuel pressure regulator back to the intake.

Do a before and after tell us, if it matters in the real world
 

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If you take the intake tube off, and look and feel the inside you'll be able to see/feel for yourself that design doesn't interfere with the flow of air into the engine. The device is for sound suppression, removing it will likely not do anything to improve performance. But it will cost you a few pennies in buying plugs for the holes and extending the vacuum line off the fuel pressure regulator back to the intake.

Do a before and after tell us, if it matters in the real world
I think it's really a sound only mod. Slight gains maybe with both your mod and this one.


Sent from my iPhone using Autoguide.com App
 
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