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Discussion Starter #1
So I did some research about using the hemi long stem IAT sensor as an option for an upgrade, if you will, for 3.6 engines.

Some said they read different values, some say don't work, some have done the change with no ill effect.

So what's really going on.

Parts tested:

- My original 3.6 IAT with 17,000 miles
- A very used 3.6 IAT with 55,000 miles
- New long stem 5149279AC from Steve White Motors

1. Test- verify both ohm meters to read the same on each IAT, both OHM meters read same number with in .02 ohms, got be really still for numbers to match, so no differences between meters.

2. Heated mug of water in the microwave, placed both sensors( 17,000 mile short unit and new long stem) into approx. 180 F degree water, Short IAT sensor 1.15 ohms, Long IAT 1.18 ohms

3. Let water cool off to approx. 160 F and short IAT 1.85 ohms, long 1.87 ohms

4. Dry both sensor down with hair dryer at same time, let both sensor cool off to room temp approx. 77 f degrees til both ohms measurements stabilize, short 17,000 mile IAT 10.63 ohm, long 10.47 ohm.

5. Place both short IAT sensors into approx. 180 F water, short 17,000 mile IAT 1.38 ohms, 55,000 mile IAT sensor 1.35 ohms

6. Let water cool down place both in approx. 160 F water, 17,000 mile IAT 1.81 and 1.83 ohm for the 55,000 mile unit.

7. Unhooked the 55,000 mile unit -replaced with long stem real quick ,place the 17,000 mile short and the long stem into approx 148 F water, short 2.24 ohms and the long 2.26 ohms

8. Unhooked the long stem and put on the 55,000 mile unit , let both short units come to room temp approx 77 F after a short dry off with hair dryer, the short 17,000 mile unit is at 10.37 ohms and the 55,000 unit is at 10.67 ohms


9. Last test- room temp approx. 77 F, new long stem IAT sensor 10.60 ohms and the older 55,000 mile short IAT sensor 10.74 ohms.


So, to me it looks like any given sensor there is a little difference, nothing perfect, while let them cool off to room temp between any given two there was at times .50 ohms difference, didn't matter long or short, short and short, they varied some while cooling off, at room temp there is a difference in all 3 units.

To me it looks like all three are doing there job and I played with each one going back and forth between meters and they was the same between the meters within a .02 ohm, they are touchy a little you can move them around a little and they change ohms some because of the air moving over the tips.

So to me, I'm not seeing any harm in running the long stem hemi IAT sensor in the 3.6 engines.

What are your thoughts on what I tested above?

Looks like the older 55,000 mile unit shows some mileage in ohm readings. So it looks like maybe even getting a new IAT sensor will help in keeping things a little closer, don't know, heck there's probably just as much variance between new units as these three.
 
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Discussion Starter #2
So I thought I would share a picture, I built a wire harness to plug into the factory IAT sensor harness, this harness in the picture I can now run either the short IAT or the Hemi long stem.

I tested all three IAT sensors I had, in this wire harness adapter, the 55,000 mile IAT sensor reads 12.85 ohms of resistance and I switch it out to my 17,000 IAT I have been running and it reads 12.47 ohms and then I unplugged that sensor and plugged in the long stem and it read 12.28 ohms. Which is inline with previous testing above, only this time I'm using one meter and one wire harness. It was just the resistance at room temp. I not going thru the whole ordeal again, I know these IAT sensor do the same work/read, just two different designs.

So the 55,000 mile IAT sensor I will not use, looks like the older these sensors get more they build resistance. So I will save it for a back up just in case I break my original one.

I talked with Jay the tuner from Sprintex Superchargers and it appears he has no issue running this long stem on the 3.6, but one needs to be aware that if you have a custom set up that deems it necessary to run the longer stem, it's an option, if you just stick this in the stock 3.6 pentastar intake tube, it looks like you would go past center and just end up reading temps from the other wall.

Hope this helps someone who might be looking into this as an option.
 

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The Pork Wagon (‘14 Cop Charger)
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So I thought I would share a picture, I built a wire harness to plug into the factory IAT sensor harness, this harness in the picture I can now run either the short IAT or the Hemi long stem.

I tested all three IAT sensors I had, in this wire harness adapter, the 55,000 mile IAT sensor reads 12.85 ohms of resistance and I switch it out to my 17,000 IAT I have been running and it reads 12.47 ohms and then I unplugged that sensor and plugged in the long stem and it read 12.28 ohms. Which is inline with previous testing above, only this time I'm using one meter and one wire harness. It was just the resistance at room temp. I not going thru the whole ordeal again, I know these IAT sensor do the same work/read, just two different designs.

So the 55,000 mile IAT sensor I will not use, looks like the older these sensors get more they build resistance. So I will save it for a back up just in case I break my original one.

I talked with Jay the tuner from Sprintex Superchargers and it appears he has no issue running this long stem on the 3.6, but one needs to be aware that if you have a custom set up that deems it necessary to run the longer stem, it's an option, if you just stick this in the stock 3.6 pentastar intake tube, it looks like you would go past center and just end up reading temps from the other wall.

Hope this helps someone who might be looking into this as an option.
So the longest sensor in that pic is for the V8s only? I was thinking all the 2011+ engines came with that one, as it was an upgrade to the stubby little pieces of crap that the 2010 and below models used.

I have been thinking about running one of the 2011 sensors in my 2010's engine to take advantage of the more precise temperature feedback they give (less susceptible to heat soak/bleed it off more quickly than 2010 and below), but I have been a little worried about cutting into the factory wiring harness and soldering in another plug to handle the newer sensor (they aren't interchangeable in the wiring harness). But if you've done that and have not seen any major interference issues or similar electrical problems with it, I think I might have to try it soon.
 

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Discussion Starter #4
So the longest sensor in that pic is for the V8s only? I was thinking all the 2011+ engines came with that one, as it was an upgrade to the stubby little pieces of crap that the 2010 and below models used.

I have been thinking about running one of the 2011 sensors in my 2010's engine to take advantage of the more precise temperature feedback they give (less susceptible to heat soak/bleed it off more quickly than 2010 and below), but I have been a little worried about cutting into the factory wiring harness and soldering in another plug to handle the newer sensor (they aren't interchangeable in the wiring harness). But if you've done that and have not seen any major interference issues or similar electrical problems with it, I think I might have to try it soon.
The long stem is the Hemi IAT sensor, the short is what is in the 3.6 pentastar engines use, I just checked the ohms again, between the sensor and the connection plug to the harness to double check my soldering job, same numbers, before I did this job I checked a couple of scrap pieces I put together to make sure there was no resistance in my solder work.

I would get the long stem and one of the pigtails and just strip your wiring on your factory harness back and solder on the pigtail without ever cutting off the original connection- don't break the factory wire so it's not cut in half, so just in case you run into issues you can always install the factory IAT, kinda do what I did, have the option to go either way with the IAT.
 
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So the longest sensor in that pic is for the V8s only? I was thinking all the 2011+ engines came with that one, as it was an upgrade to the stubby little pieces of crap that the 2010 and below models used.

I have been thinking about running one of the 2011 sensors in my 2010's engine to take advantage of the more precise temperature feedback they give (less susceptible to heat soak/bleed it off more quickly than 2010 and below), but I have been a little worried about cutting into the factory wiring harness and soldering in another plug to handle the newer sensor (they aren't interchangeable in the wiring harness). But if you've done that and have not seen any major interference issues or similar electrical problems with it, I think I might have to try it soon.
There is a pretty detailed thread on challengerformz that discusses the differences. At least for the V8s. The V6 has what appears to be a slightly different IAT (at least in appearance) than the short IAT for the V8.

https://www.*********************/threads/long-iat-vs-short-iat-senser.90343/
 

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Discussion Starter #6
There is a pretty detailed thread on challengerformz that discusses the differences. At least for the V8s. The V6 has what appears to be a slightly different IAT (at least in appearance) than the short IAT for the V8.

https://www.*********************/threads/long-iat-vs-short-iat-senser.90343/

I read that thread, that's why I wanted to get to the bottom of it, to see if it's an option for the 3.6 but as you can see in my test results the two sensor are the same - 3.6 short to hemi long stem, they read the same resistance in the same temperature environment.

If fact I just got done playing with the two sensor long and short on my 3.6, I plugged my new made wire harness in and did some A-B-A test from 0-60, after 15 pulls on the same road, right now my times are in favor of the long stem, not because I want them to be, because that's what the car is saying for right now.

So I'm not going to stop there, I just wanted to see if there is any possible performance difference between the two on my car 0-60 mph, the long stem is providing me with a clear picture of better 0-60 mph runs.

Today my best run was 4.10 0-60 mph with the long stem, best run on the short IAT was 4.23, the long provided me with several pulls between 4.10 and 4.20, where as the short IAT was pretty grouped up in the mid 20's.

Next couple of days or so I'm going to data log to see if I can see why I'm a little quicker with the long stem.

One thing I did notice, when I was swapping out IAT sensors, the long stem was real cool to the touch.

Thought I would share my findings.
 

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Discussion Starter #7
I thought I would add, I put the long stem in the stock 3.6 air tube, the long stem goes to center, thanks to the large mounting boss, being the stock tube is about 3 1/4" round I thought the long stem would almost reach to the other side, but it don't.
 
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