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One, final warm-air intake question

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Ok, I am ready to do the flex-tube mod that basically moves the intake to above the cat, in order to take in the warm air radiating off of the cat. My question is this: Where is it best to connect the flex-tube to? I see three possbilities. 1) at the "horn( the end that kinnda looks like trumpet end)" that is the current intake, 2) or remove the horn and attach the flex tube between the filter box and original "horn" location or 3) connect the flex-tube right at the air box(there is about a 2 inch collar which the tube fits nicely over).
Which one is best? Do I need to be concerned for that tube wich runs straight down from the main intake plumbing (what is that, it looks like it has a shock absorber boot on it)? Sorry for being long-winded, thanks for any input.
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Choose #3
3) connect the flex-tube right at the air box(there is about a 2 inch collar which the tube fits nicely over).
Then you'll want to run the other end of it towards the driver's side of the car.
Next route it underneath the battery box, snaking it towards the passenger's side until the open end ends up right next to the upper catalytic converter.

What to do about the stock air intake hose?
I just leave it dangling there for future -reuse.

Premium Member
4,838 Posts
I haven't looked under the hood in a while now so I am not understanding how you are confused in there being 3 choices. Leaving the existing horn on makes fitting a new tube somewhat of a problem, but if you've got one that fits go for it!

Removing the tube as I did (see my web page link in my signature) seemed the easiest.

The "straight down tube" I believe you are referring to would be part of the intake's "tuning" and would likely have the greatest negative impact in potential MPG (although only slight). And we are _slightly_ shifting the power and torque curves of the ICE by changing the effective length of the intake anyway.

I doubt there is a wrong way. The "wronger" ways will cause damage of other parts due to chaffing or needed modification, self destruct due to chaffing on inconsequential parts, or have an insufficient increase in intake temperature.

And remember no pain no gain! The increased IAT will only _help_ widen the lean burn window. If you don't drive in the maximum MPG style you'll never be within this window of opportunity anyway. Best MPG improvements for this modification are seen in late fall through early spring (cool temperatures). :)

Hi Brpeterson:

___The place to connect it up is at the air box with the plastic horn (at the air box side) removed. You will see a snap ring at that location if you need even further guidance. After removing the snap ring, pull the OEM horn’s 2” diameter connection away and let it hang. Then connect up your 6’ of flex tube and route it back to the CAT shield or pick up Insightful_Trekker’s F150 piece for the exhaust pipe itself and connect it up there. There is also a place to stuff the outlet of your flex tube in between the plastic ICE cover and the ICE itself with a similar effect.

___Anyway, don’t just use a 4’ section as you are really stretching it, use (2) 3’s connected up to one another for a 6 footer. Once you open up the hood, it will make sense as to where you will run the tubing. I installed mine blind in the parking lot of a SD. Honda dealer when I picked her up so you can well imagine that you are worrying way too much right now! Don’t forget to use 1 or 2 heavy plastic Zip ties to hold it in place. Don’t synch them up enough to crush the tubing but just tight enough to hold it in place. Do not zip tie it up near the air intake box either as you will remove it eventually … I use a screw clamp on the air box to flex tube connection for mine if that helps but I carry a small screwdriver and a few tools with me at all times just in case as well?

___And don’t forget that it won’t really add much and can even reduce your mileage when you are driving in summer time temps. I haven’t driven in anything over 84 degrees F so far but if I ever see a sustained 85 + from start to finish location ( --> Location --> Hourly will give you all you need to know ;)), I will remove the warm air intake mod at the air intake box and install the std. tuned intake horn back on for maximum mileage. 30 seconds max.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:3dpffyms][email protected][/email:3dpffyms]
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