[Hal H]

I switched to the "Charger Tube" which comes with the long sensor, a few years ago.

I can't data log, but I can see the two different temps on my EVIC. Depending on the outside air temp, they both can read within a few degrees of each other. With hotter ambient, on the road, temps usually with in 10-15. Hot and long idles, I've seen up to 30 for a few minutes.

Have no idea what the voltages are, just the EVIC readings, but the car seems to run fine or a little better than when it had the stock tube/goiter.

???

John -

Those EVIC readings are:
- external air temp (not IAT)
- coolant temp (hidden EVIC screen)
- Oil temp (typically runs a few points above coolant @ slower driving speeds/stop & go).

The IAT sensor readings are accessed using a tuner or ODB-II scanning tool.

 

[19johned53]

John -

Those EVIC readings are:
- external air temp (not IAT)
- coolant temp (hidden EVIC screen)
- Oil temp (typically runs a few points above coolant @ slower driving speeds/stop & go).

The IAT sensor readings are accessed using a tuner or ODB-II scanning tool.

Hmmmm. On my hidden EVIC display, I have on setting that just shows TEMP AVE= and a TEMP RAW=

These are the two that I was talking about above on the range. On another hidden menu its shows Eng temp/oil temp and a few other things.

Guess that I assumed that the TEMP AVE and TEMP RAW was external and IAT temps.

Anyways, I really can't say that the car runs worse with the Charger tube and long IAT, If anything, I thought at first that some of the bog/heatsoak effects were less than the stock unit. I'm used to it now, and seems to run as good as ever.

 

[rayzazoo]

A local tuner says the long sensor gives false readings to the 09 and 10 Challengers, so I put my back to stock.

"Old sensor 2volts = 90 deg F and on new 2volts = 60 deg F"

I think the data shows otherwise: both share relatively the same temperature vs. time curves as illustrated below.

Further, both sensors reach within the same 2-5 deg F within ambient at a steady 70mph cruise.

The thing that stands out as a difference between the two is how they react to temperature during a WOT run as illustrated below. Something caused the Short 2010 sensor to keep at a high temperature during a WOT run vs the Long 2011+ sensor that gradually reduced it's reading through the WOT run. Both sensors started within 7 degrees upon initial entry in to the WOT run and both eventually came to the same close to ambient temperatures thereafter (you can also see how both sensors steadily climbed at similar rates after the WOT runs). The only thing that could make a change to the electric current flowing through the thermistor, and thus the change in temperature reading, is airflow over the sensor, the effects of radiant heat from the surrounding environment, and the dissipation of heat from the sensor itself.

In all, the newer sensor acted more quickly to changes in temperature and airflow. During WOT, the most critical time for engine performance, there is a drastic change in temperature and airflow and I'd want the sensor that also registered that change during the run (new) rather than the one that was still registering residual heat (old).

 

[DTru]

Further, both sensors reach within the same 2-5 deg F within ambient at a steady 70mph cruise.

I think that is the clear indicator. They are going to read differently at times because the long sensor is more accurate (thats why they are on the new vehicles), but if it consistently reads the same range above ambient while cruising then that tells me that there is no change in how the computer reads the voltage.

 

[Hal H]

Hmmmm. On my hidden EVIC display, I have on setting that just shows TEMP AVE= and a TEMP RAW=


Guess that I assumed that the TEMP AVE and TEMP RAW was external and IAT temps.

Anyways, I really can't say that the car runs worse with the Charger tube and long IAT, If anything, I thought at first that some of the bog/heatsoak effects were less than the stock unit. I'm used to it now, and seems to run as good as ever.

The temp RAW and temp AVG are the ambient sensor readings - the AVG is delayed / averaging readings, so that it isn't fluctuating (like being at a stop light vs. moving), since the underhood heat would throw off the readings some.

 

[19johned53]

Thanks Hal

 

[Crush]

Rayazoo - thanks for posting the graphs and information. But my question is this: if its true that the old and new IAT sensors have different transfer functions, that means one of them is sending false information to the pcm. In the data logs above, aren't you logging the pcm information? If one of them is false reading, we can't count those temps as accurate.

I think we need to verify that the two sensors have the same transfer functions first, otherwise we need anther constant to measure the temps.

Can these IATs be tested on a "bench" outside the car to see if the temps and voltage fluctuations match?

Not trying to be controversial, just trying to get some questions answered. :scratchhead:

 

[DTru]

Rayazoo - thanks for posting the graphs and information. But my question is this: if its true that the old and new IAT sensors have different transfer functions, that means one of them is sending false information to the pcm. In the data logs above, aren't you logging the pcm information? If one of them is false reading, we can't count those temps as accurate.

I think we need to verify that the two sensors have the same transfer functions first, otherwise we need anther constant to measure the temps.

Can these IATs be tested on a "bench" outside the car to see if the temps and voltage fluctuations match?

Not trying to be controversial, just trying to get some questions answered. :scratchhead:

If the IAT's are consistently 2-5 above ambient while cruising then that is proof that the transfer functions are the same.

 

[Crush]

If the IAT's are consistently 2-5 above ambient while cruising then that is proof that the transfer functions are the same.

I agree that seems reasonable, and I also think the 2011 IAT design is much better, that's why I used one for so long. But wouldn't you want to know for sure that the two sensors have the same transfer functions esp if you are paying somebody for a custom tune?

 

[DTru]

I agree that seems reasonable, and I also think the 2011 IAT design is much better, that's why I used one for so long. But wouldn't you want to know for sure that the two sensors have the same transfer functions esp if you are paying somebody for a custom tune?

Is there any other way to test it? I guess you could pull out the sensor, connect each one and see how close they come to the ambient temp but your car would have to be running to get the information and I dont think anyone would want to run the vehicle without the sensor in the intake.

 

[rayzazoo]

Is there any other way to test it? I guess you could pull out the sensor, connect each one and see how close they come to the ambient temp but your car would have to be running to get the information and I dont think anyone would want to run the vehicle without the sensor in the intake.

You could measure what the voltage is transferring through the wire with a voltmeter and a current, however, the PCM dictates the voltage vs temperature reading (as mentioned, under similar operating conditions, both sensors produced the same 2-5 deg above ambient temperatures). The sensor is simply a resistor and limits the amount of current transferring through one wire to the other.

If it helps, both are a 5 volt thermistor and both have the same max/min temperature range. The only factors that are left to influence the sensor are heat dissipation and environmental heat (conducted airflow and radiated/conducted heat from the intake tube).


Sent from AutoGuide.com App

 

[BWD]

Doesn't read too much higher than ambient, some is to be expected. This is stock air box.

That was this morning with the new sensor. Yesterday it was 100 driving home and my stock sensor read 185 degrees at one point. Should be the same temp on the way home today so I'll tst again.

i cant get this app to work for me.

 

[Part Deux]

connector body and seal are available from Mouser.com without a minimum order. Terminals still have a minimum qty order.

Why is Diablo stating (heard from Speedlogix) the long sensors cause tuning problems? Rep at Speedlogix couldn't tell me why.

 

[70barcuda]

I haven't looked at this thread in a while, but it still has lots of good relevant information. Upon rereading the original post it came to mind that although we have a number of examples of folks doing dyno tests on the Frankentake and Speedlogix style CAI, generally showing a 9-11 hp gain, I don't think I've seen a dyno test on the LMI true CAI. Presumably it is greater as it usually is accepted as a superior design, but I'm just wondering if anyone has done an actual dyno test of one and have any stock vs LMI CAI hp gain results.

 

[GP70]

I haven't looked at this thread in a while, but it still has lots of good relevant information. Upon rereading the original post it came to mind that although we have a number of examples of folks doing dyno tests on the Frankentake and Speedlogix style CAI, generally showing a 9-11 hp gain, I don't think I've seen a dyno test on the LMI true CAI. Presumably it is greater as it usually is accepted as a superior design, but I'm just wondering if anyone has done an actual dyno test of one and have any stock vs LMI CAI hp gain results.

I have yet to see any dyno numbers either,searching various forums.In the meantime running the Frankentake.

 

[rayzazoo]

I have yet to see any dyno numbers either,searching various forums.In the meantime running the Frankentake.

The dyno numbers are very similar to the Frankentake. The benefit of the fender pull is about 25-30 deg F less intake temperatures from a stop n go scenario. At the track, this is big as you'll get consistency with a fender pull. The down side is filter accessibility.

On a slightly different note, my neighbor has an '06 Dodge Daytona R/T. As he said, he just "fell in love with his car again", after I showed him how to do the key trick, disable BAS/ESP and do a rolling burnout. Needless to say, the grin on this ol' retiree's face was priceless!

 

[Part Deux]

The dyno numbers are very similar to the Frankentake. The benefit of the fender pull is about 25-30 deg F less intake temperatures from a stop n go scenario. At the track, this is big as you'll get consistency with a fender pull. The down side is filter accessibility.

On a slightly different note, my neighbor has an '06 Dodge Daytona R/T. As he said, he just "fell in love with his car again", after I showed him how to do the key trick, disable BAS/ESP and do a rolling burnout. Needless to say, the grin on this ol' retiree's face was priceless!

Rolling burnout?

 

[rayzazoo]

Rolling burnout?

The first 15 seconds of this video sum it up nicely.

https://www.youtube.com/watch?v=_tSThKYnOVY

 

[Part Deux]

With the changes I've made, which are relatively minor, I don't even bother with the key, torque spins right past traction control
Predator
93 octane and tune
LMI
delete center muffler
delete cat
new IAT probe

 

[Dex]

Lots of pretty fascinating info here....

What's the situation with the 2015/2016 cars? Is the IAT sensor in those of an improved type or one which should be swapped out?