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Discussion Starter #1 (Edited)
Just wanted to post my findings for anyone else that was interested.

I was very hesitant to purchase an intake that relocated the IAT sensor for fear of it "tricking" the computer into reading lower temps, but after a LOT of research I decided to pull the trigger and test it out for myself. Once I placed the order I started to do some logging of the stock set up to monitor temps. I have a 60 mile round trip commute to work every day so I logged two days running stock, then two days running the fender pull. The drive is nearly all highway with 3 stop lights near the beginning and end. Luckily I had one day of traffic and one day of open road for each log. These are just the numbers I found most interesting so if anyone would like the actual logs just shoot me a PM. Keep in mind these are average temps of the whole trip. Logs were taken with a Trinity.

13 RT
Speedlogix/Zoomers cat back
2011 Charger RT intake tube
K&N Drop in
392 chin spoiler w/o brake duct funnel
baffle delete mod
functional hood scoops

Log Name....................Ambient....Intake.....Manifold
To Work Stock 1..............85.96.....90.52........99.85
To Work Stock 2..............86.20.....91.46......100.46

To Work LMI 1.................85.25.....86.16........95.90
To Work LMI 2.................85.43.....86.55........96.17

Ride Home Stock 1..........105.70....119.16......127.75
Ride Home Stock 2..........105.77....113.73......121.26

Ride Home LMI 1.............105.64....111.04......119.95
Ride Home LMI 2.............109.00....112.23......120.79

You can make your own conclusions with the provided numbers but what I found most interesting (and reassuring) is that the average difference between the intake temperature and the manifold temperature were nearly identical. The averages were so close there was only half a degree difference which can be chalked up to many different variables. This confirms that moving the IAT does not "trick" the computer into thinking its taking in cooler temps.

The average intake temperatures dropped by 3.9 degrees on my morning drive and by 6.4 on my way home during the 100+ temps.

Also, something else that I have noticed, the new intake recovers from heat soak several MINUTES faster than stock. After sitting at a light in the afternoon my intake temps were reaching up to 150, with the stock set up it would take 6 minutes of driving at 60+ for the temps to drop down to near ambient. With the LMI it takes less than a minute.

Hope someone will find this useful.

Edit: Attached a picture of my intake air temp reading while cruising at 70mph.
 

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Nice data collection!...and man does it get hot in that intake manifold! :eek:
 

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Imagine the 6.1 manifold then. I bet that sucker heat soaks a ton.
 

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Just wanted to post my findings for anyone else that was interested.

I was very hesitant to purchase an intake that relocated the IAT sensor for fear of it "tricking" the computer into reading lower temps, but after a LOT of research I decided to pull the trigger and test it out for myself. Once I placed the order I started to do some logging of the stock set up to monitor temps. I have a 60 mile round trip commute to work every day so I logged two days running stock, then two days running the fender pull. The drive is nearly all highway with 3 stop lights near the beginning and end. Luckily I had one day of traffic and one day of open road for each log. These are just the numbers I found most interesting so if anyone would like the actual logs just shoot me a PM. Keep in mind these are average temps of the whole trip. Logs were taken with a Trinity.

13 RT
Speedlogix/Zoomers cat back
2011 Charger RT intake tube
K&N Drop in
392 chin spoiler w/o brake duct funnel
baffle delete mod
functional hood scoops

Log Name....................Ambient....Intake.....Manifold
To Work Stock 1..............85.96.....90.52........99.85
To Work Stock 2..............86.20.....91.46......100.46

To Work LMI 1.................85.25.....86.16........95.90
To Work LMI 2.................85.43.....86.55........96.17

Ride Home Stock 1..........105.70....119.16......127.75
Ride Home Stock 2..........105.77....113.73......121.26

Ride Home LMI 1.............105.64....111.04......119.95
Ride Home LMI 2.............109.00....112.23......120.79

You can make your own conclusions with the provided numbers but what I found most interesting (and reassuring) is that the average difference between the intake temperature and the manifold temperature were nearly identical. The averages were so close there was only half a degree difference which can be chalked up to many different variables. This confirms that moving the IAT does not "trick" the computer into thinking its taking in cooler temps.

The average intake temperatures dropped by 3.9 degrees on my morning drive and by 6.4 on my way home during the 100+ temps.

Also, something else that I have noticed, the new intake recovers from heat soak several MINUTES faster than stock. After sitting at a light in the afternoon my intake temps were reaching up to 150, with the stock set up it would take 6 minutes of driving at 60+ for the temps to drop down to near ambient. With the LMI it takes less than a minute.

Hope someone will find this useful.
Did similar testing only with the Mopar CAI and I was seeing about a 6 to 7 degree delta between ambient and IAT. Seems the LMI cools faster than the Mopar after it has heat soaked as it took almost 90 seconds at 50 MPH for the IAT to get within 6 degrees of ambient.
With water/meth injection it takes 6 to 8 seconds to go from 146 to 70 in 90 degree heat. The manifold drops just as fast and as much. Still haven't been able to benefit from it though. One would think that more fuel and timing would show some results but I haven't seen it. I wonder if it has to do with the cam phaser in the VVT 392s.
Nice write up and it agrees with others findings.
 
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just curious and maybe i missed it, but for your ambient temp numbers....were you getting those from the pid in data view or just recording it off the dash temp gauge?

nice collection of data by the way. i did a similar test between the long and short IAT sensor. rayzazoo has done extensive testing in this area too.
 

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Discussion Starter #6
These are all off the PID's.

Thanks for the info KJ
 

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I am preparing to do the same today with the Mopar CAI down @ the Woodward Dream Cruise. The temps are sure to get very hot with all the stop and go traffic..
Im PMing you, I would like to look at your full logs...
 

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DTru - great data, thanks!

I would be very interested in seeing a strictly in town test, with the AC on - that's when I experience the heat soak most.

I had extended idling with the AC on in 95 degree heat the other day, and when I got on the open road, going through the gears it felt like I was pulling a boat. I do have the roto-fab and 2011 IAT sensor (which helped a lot). Running the AC seems to compound the problem.

Did you feel any performance diffence between the two setups?
 

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Discussion Starter #9
Ill try to send the logs to you tonight BADHEMI
 

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Discussion Starter #10
sorry for the delay, i tried to upload but i keep getting errors
 

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Discussion Starter #11
Badhemi,
Did you ever test the Mopar CAI?
 

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Running heat extractors (louvers) on the hood is one of the best options you can get for under the hood temp!!
 

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I wonder how much the functional hood scoops do to lower the temp, they seem to channel air down and behind the engine to help the air flow.
 

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I wonder how much the functional hood scoops do to lower the temp, they seem to channel air down and behind the engine to help the air flow.
I am curious as well, because i am debating whether to buy them or not.
 

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Air is dirty, Air is oily, engine bay gets dirty faster and dirt holds heat!!! If you want under the hood Temps to be lowered you need hood extractors like the GT500 or the Hellcat any thing else is a Wast!!!
 

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Well, you do make a point but I am not going to take them off, they came with the car!
 

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no sense of taking them off if you have them all ready... I have a base R/T, so I don't need to buy them for anything but I can tell you one thing if I had an SRT 394 I would get extractors like the hellcat only because SRT'S run really hot compared to the R/T's...


I also hear taking off the brake fluid cover helps but I don't know if air gets in or out... I would guess it would act like a cowl induction for the engine bay.. I had read an article about extractors how it help the down force and cooling of the vehicles at the same time..
 

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\
I also hear taking off the brake fluid cover helps but I don't know if air gets in or out... I would guess it would act like a cowl induction for the engine bay..
Your're not serious...right?!!:icon_eek:
 

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Your're not serious...right?!!:icon_eek:
i think he's referring to the black cover on the cowling, and not the reservoir cap. some guys on lxforums did some testing with airflow under the hood and found if they remove that black cover, it cools the engine bay down quicker.
 
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i think he's referring to the black cover on the cowling, and not the reservoir cap. some guys on lxforums did some testing with airflow under the hood and found if they remove that black cover, it cools the engine bay down quicker.
Ah! Thanks for clearing that up!...before someone (like me) actually removed the reservoir cap! LOL!
 
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