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Discussion Starter · #1 ·
After being bored and taking all the plastics off the engine and staring at the airbox setup for quite a while. I have determined that I do not like how little airflow there is through the factory scoop, and how the secondary intake seems to suck whatever air it gets from the engine bay.

I think I'm going to get a K&N intake, throw away the lame heat shield that they have, and make a custom airbox and possibly a scoop out of thin sheet metal.

I'll keep this updated.
 

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I just installed a K&N intake 2 days ago. The best way to discribe the experience is the car now sounds,,,,,ANGREY! ( in a good way)
I agree that the provided heat shield is rikkedy and have thought of making my own. It seems there is a lot of room in the empty air box mounting area,,,,but not many options to retrieve or route fresh air through.
Are you thinking of a sealed bow with the single fresh air scoop "sealed" to it?
 

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Discussion Starter · #3 ·
i was thinking of closing off the 4 sides around the filter. the bottom, the top, the area facing the suspension and the area where the intake pipe goes. then after that is complete possibly seeing how much more fresh air scoop i can get out of the tiny area. probably not much but we'll see
 

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I think the secondary air inlet pulls air from the fender well, it's still a cold air intake. I don't think it pulls from the engine bay.

Post pics of your idea, you might be on to something!
 

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Discussion Starter · #5 ·
I think the secondary air inlet pulls air from the fender well, it's still a cold air intake. I don't think it pulls from the engine bay.

Post pics of your idea, you might be on to something!
the secondary inlet opens towards the fender and the hood. however there is no air scoop in that area. so it pulls whatever air it gets. and that air is going to be from under the hood.
 

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Bedfore you go through all this fabricating you should actually monitor the AIT. Everyone thought they could improve on the IS350 intake box and after testing, it functions perfectly as a cold air system in stock form (adding a Joe Z does help). I personally tested the AIT and it was 1 degree warmer or less at WOT. Just a thought.


P.S. Here is a fun pic for reference.

 

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the secondary inlet opens towards the fender and the hood. however there is no air scoop in that area. so it pulls whatever air it gets. and that air is going to be from under the hood.
That is incorrect...

The fender liner has been fabricated to allow air flow when called for by the intake. Check it out..

The passenger side has openings, while the drivers side does not.. ;)

Cooler air is drawn out of the fender.

Regards,
Joe Z
 

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Discussion Starter · #8 ·
yes i was detailing my car this morning and i took a closer look. either way, making a better heat shield that covers 4 sides of the air filter from the engine bay could only improve efficiency.
 

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Discussion Starter · #9 ·
this has nothing to do with customizing the intake. but k&n should send out a warning how loud this thing is. seriously it is retarded loud and i LOVE it lol
 

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I will second that its is sooooo loud but fantastic, scary scary loud but around town under 2000rpm quite as a mouse :)
 

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this has nothing to do with customizing the intake. but k&n should send out a warning how loud this thing is. seriously it is retarded loud and i LOVE it lol
Any audio clips for us? Also any estimate on HP gains for this or the Lexus Performance Intake? And how much$ was you K&N?
 

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Discussion Starter · #12 ·
Any audio clips for us? Also any estimate on HP gains for this or the Lexus Performance Intake? And how much$ was you K&N?
the guy at autoanything got me the intake for 255US + 45US shipping to canada. best price i found.

i dont have a good quality microphone. i tried my digital camera, but it doesnt sound anything like how it sounds in person. ur just gonna have to trust the people who have it. its quiet when normal driving, half throttle its about as loud as the stock intake at wide open, and wide open its ridiculous loud, so much that u cant hear the stock exhaust.

k&n sends a dyno graph saying 28whp increase. i highly doubt that it produces that much more. but it is noticeable around the top end definately.
 

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That is incorrect...

The fender liner has been fabricated to allow air flow when called for by the intake. Check it out..

The passenger side has openings, while the drivers side does not.. ;)

Cooler air is drawn out of the fender.

Regards,
Joe Z
why dont u make a tube coming from fender just to the second intake? or even from the brake ducts? i get the first one! :)
 

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Just for shiggles, anyone in the DFW area want to test the IAT of the factory intake box? I am curious to see how it does with ambient air. I have the meter to read it, just need you to drive around while I watch it....
 

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Just for shiggles, anyone in the DFW area want to test the IAT of the factory intake box? I am curious to see how it does with ambient air. I have the meter to read it, just need you to drive around while I watch it....

AND a K&N comparison too. Anyone? This is a great chance to compare the stocker and the K&N, put this argument to rest!
 

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Bringing this back up:

Did you guys ever get those IAT temps? Id really like to see which one is really cooler
 

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Discussion Starter · #17 ·
I actually can monitor IAT now, I plug my laptop into the car quite often to look at things since I've put headers on. The intake air temps are pretty similar while cruising around town. I've judged this to be from the headsoak heating the tubes from the airbox to the throttle body. As soon as you make it suck in air, they drop quite quickly, but still remain higher then ambient temperature by about 10C or so, depending on the day.....

All in all, the stock airbox has lower temps. I also noticed that the car has more timing advance with the stock airbox.

I also made the brake duct intake, leaving the brake duct fully functional. Basically all it did was lower the IAT a little faster with the K&N. Right now I have the stock airbox on however because I have been testing my theories with the timing advance and whatnot. I never paid too much attention to the mass air flow rate, I should have been more diligent...
 

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Thanks for your info. Have you ever wanted to test out other F's with different intake set ups?
 
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