Does a cold air intake add power on a 4.0?

Why is that I have a York and still run the stock air box ?
Don't believe me eh? Because some model years require that the York compressor be located in a different location due to different a/c compressor/alternator locations. Kilby's first York OBA mounting bracket was designed for the '97 TJ, that's what I used.

So my '97 required that I remove the OE air box.

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I wouldn't run a K&N filter on any of my vehicles if it added 50HP.
X2. It's amazing how some take K&N's hype at face value and refuse to believe how much additional dirt they let into an engine. They might be ok for pavement pounders where there's not much dust in the air but it'd be a big mistake to run one offroad where there's a lot of dirt and dust in the air. Not to mention that at least with a TJ and its OE air intake box, they add ZERO power. For the reason that has been mentioned here too many times over the years to bother to say it again.
 
Don't believe me eh? Because some model years require that the York compressor be located in a different location due to different a/c compressor/alternator locations. Kilby's first York OBA mounting bracket was designed for the '97 TJ, that's what I used.

So my '97 required that I remove the OE air box.

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Yea that is different than mine

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Not to mention that at least with a TJ and its OE air intake box, they add ZERO power.
This is where I'm confused. I know you have your vast seat of the pants experience and you've talked to your engineer friend and everything who told you so, but you did see the first post, right?

I have agreed with you time and again that any sort of intake is not going to have a noticable difference in performance for any "stock" 4.0, especially in the rpm range most (sane) TJ drivers stick to or care about. And nobody is arguing about the filtration efficacy (or lack there of) of a K&N type oiled filter. In respect to them making no power and being pointless because the stock system is so great to begin with, you are drinking a little too much of the Kool aid you are peddling to others.
 
I would never do one again. Nothing but trouble on my Tacoma. Instant check engine light, and terrible gas mileage. I threw the stock one away quick like a fool a long time ago. Like Jerry said the KnN filter is like a window screen that you can see thru. I like the stock airbox on my 2.5.
 
This is where I'm confused. I know you have your vast seat of the pants experience and you've talked to your engineer friend and everything who told you so, but you did see the first post, right?

I have agreed with you time and again that any sort of intake is not going to have a noticable difference in performance for any "stock" 4.0, especially in the rpm range most (sane) TJ drivers stick to or care about. And nobody is arguing about the filtration efficacy (or lack there of) of a K&N type oiled filter. In respect to them making no power and being pointless because the stock system is so great to begin with, you are drinking a little too much of the Kool aid you are peddling to others.
I'll repeat this again for more redundancy. I have a 99. For a couple of years, we went to Big Bear every weekend that was not winter and a few in the winter. Same trip along the toll road. Last toll booth is at the top of a long hill. With the cruise control set at 65 it would invariably downshift to second right even with a particular sign without fail.

I added several things one at a time. All the typical stuff, CAI, High flow filter, high flow exhaust. But only one thing at a time.

Each item would work very well the first trip over the hill and delay the downshift by a noticeable margin sometimes even pulling the hill to the top in drive. The next trip it would be right back to downshifting into second at the exact same spot.

32RH, geared to 4:10's on 33's.

Not an exact science by any means but clear enough to me that nothing I did was going to have an effect long term without programming changes.

We have the benefit nowadays of that being available, it was not back then in 99.
 
This is where I'm confused. I know you have your vast seat of the pants experience and you've talked to your engineer friend and everything who told you so, but you did see the first post, right?

I have agreed with you time and again that any sort of intake is not going to have a noticable difference in performance for any "stock" 4.0, especially in the rpm range most (sane) TJ drivers stick to or care about. And nobody is arguing about the filtration efficacy (or lack there of) of a K&N type oiled filter. In respect to them making no power and being pointless because the stock system is so great to begin with, you are drinking a little too much of the Kool aid you are peddling to others.
I'll repeat this again for more redundancy. I have a 99. For a couple of years, we went to Big Bear every weekend that was not winter and a few in the winter. Same trip along the toll road. Last toll booth is at the top of a long hill. With the cruise control set at 65 it would invariably downshift to second right even with a particular sign without fail.

I added several things one at a time. All the typical stuff, CAI, High flow filter, high flow exhaust. But only one thing at a time.

Each item would work very well the first trip over the hill and delay the downshift by a noticeable margin sometimes even pulling the hill to the top in drive. The next trip it would be right back to downshifting into second at the exact same spot.

32RH, geared to 4:10's on 33's.

Not an exact science by any means but clear enough to me that nothing I did was going to have an effect long term without programming changes.

We have the benefit nowadays of that being available, it was not back then in 99.
 
I'll repeat this again for more redundancy. I have a 99. For a couple of years, we went to Big Bear every weekend that was not winter and a few in the winter. Same trip along the toll road. Last toll booth is at the top of a long hill. With the cruise control set at 65 it would invariably downshift to second right even with a particular sign without fail.

I added several things one at a time. All the typical stuff, CAI, High flow filter, high flow exhaust. But only one thing at a time.

Each item would work very well the first trip over the hill and delay the downshift by a noticeable margin sometimes even pulling the hill to the top in drive. The next trip it would be right back to downshifting into second at the exact same spot.

32RH, geared to 4:10's on 33's.

Not an exact science by any means but clear enough to me that nothing I did was going to have an effect long term without programming changes.

We have the benefit nowadays of that being available, it was not back then in 99.
I'll repeat this again for more redundancy.

Is that why you posted it twice :ROFLMAO:
 
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I will forego arguing about the lack of exact science there as you already pointed it out. I will ask then though, if your TJ learned it's way around the power mods you did, would the issue be with the lack of effectiveness of those mods, or would it be an issue with the way the PCM works?

And yeah, the double post thing is happening to me today as well.
 
I will forego arguing about the lack of exact science there as you already pointed it out. I will ask then though, if your TJ learned it's way around the power mods you did, would the issue be with the lack of effectiveness of those mods, or would it be an issue with the way the PCM works?

And yeah, the double post thing is happening to me today as well.
This is why I tend to avoid these discussions. You know I am not the least bit unintelligent. You know I don't embellish or exaggerate and yet that's your response?

Same hill, same sign, same long pull every weekend for a couple of years and it would downshift at exactly the same spot every time. How much more fucking exact do you want that to be?
 
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