Infrared Pictures of Intake Tubes and Air Box

[Jack B]

The following infrared pictures were taken at the end of this sequence:

1. Ambient air temperature was 41F.

2. After 30 minutes of driving at 45 mph the displayed IAT was 71, that is normal for my car. That makes no sense for a car with a cold air inlet, but, it is usually plus 30 degrees over ambient.

3. The car idled for ten minutes, displayed IAT went to 93.

4. Shut the car down and waited five minutes, displayed IAT went to 125.

5. The following pictures were then taken.

The "+" sign is a marker and indicates the temp at that point. The straight line can be graphed, however, the three temps above the line are the min/mx/average. The lighter colors are hotter.


IR_00015.jpgIR_00016.jpgIR_00018.jpg

[Steve M]

So the IATs are accurate?

[01sapphirebob]

Doesnt look like it. The pictures were taken after the car was turned off. The car says that the IAT was 125 but if you look at the first pic the temp at the very from of the AI is only 97. WAY off.

[Jack B]

There are two separate issues, the IAT definitely does not correlate to ambient air at moderate speeds. My guess is that at 100 mph it is right on. However, at moderate speeds heat is being conducted into the sensor, therefore, it is not reading true IAT, which should be primarily convected heat.

You are correct, my pictures prove the IAT sensor is correct for temps after the car is shut down. Without any air flow thru the air box, the air surrounding the IAT will reach the temps shown in the pictures. Unless the IAT is moved to the front of the air box not a lot is going to change.

The core problem at the drag strip is that the car usually idles or sees an idle/off cycle, therefore, the high IAT and the PCM pulling timing. My guess is that a GTS will see higher displayed IAT temps than a SRT since it only has two hood openings. A possible solution at the drag strip is get put a thin gel ice pack over the IAT area. Once you lose the thermal inertia it will be hard to reduce the IAT quick enough to help at the dragstrip.

So the IATs are accurate?

[ACRucrazy]

Good stuff Jack! Thanks for sharing!

[Newport Viper]

Just plain Cool.... Thanks Jack

[Brian GTS]

Jack, have you submitted your resume to SRT yet? Nice work!

[donk_316]

Ok cool... so how do you fix it... Cant relocate the IAT because its combined with the MAF?

Can you use some sort of relfective insulation on the MAFs and ducting?

What about the old "resistor in the wire" trick

[ACRucrazy]

I am unsure on the Gen V, but I have seen some Gen IVs like this









The pics above are trying to force as much air through the radiator and block the hot air from getting into the intake. Also I know I have seen a Gen IV airbox covered with the DEI gold thermo wrap along with a "Tray" made below the 2 intake tubes to block heat and IIRC the tubes may have been wrapped, but I can't seem to find it. I think it was on an ACR-X.
It was this gold stuff
http://www.summitracing.com/parts/de...FadFMgodQEcAYA

[donk_316]

Ah ok! Very cool... Such a shame a $120k ++ car needs a $595 dollar part

http://www.arrowracingengines.com/arrowproducts.html

[Steve M]

Doesnt look like it. The pictures were taken after the car was turned off. The car says that the IAT was 125 but if you look at the first pic the temp at the very from of the AI is only 97. WAY off.

That's not where the IAT sensor resides.

As for the closeout panels, I don't think that's the answer either...yes, it would help keep the hot air from the radiator from entering the front of the air box, but the issue here is that the intake tract where the IAT sensors are located heat up from the engine bay. That's what needs to be shielded here, not just the inlet.

[Nine Ball]

The Gen 5 airbox seals to the hood scoop opening. Doesn't need that shield shown on the Gen 4 cars. The radiator fans blow hot air directly onto the bottom of the airbox. The right thing to do would be to build either a head shield that blocks the underside of the intake tract and airbox from the engine bay heat, or at least do some thermal insulation on the underside of the airbox and the intake tubes.

I wish we could relocate the IAT sensor to the front of the airbox, near the hood opening. That would work better. This may be a matter of figuring out what IAT sensor is used, and cutting the wires going into the MAF/IAT sensor(s) and wiring in new IAT sensors that have been relocated.

[Jack B]

Exactly, too many of these posts are going in the wrong direction. The problem is not a true high IAT, it is mostly an artifically high IAT due to under hood temps conducting heat into the oem iat sensor body.

On every other car I have logged the true iat is approx ten degrees above ambient when at speed, this car should not be way diff.

That's not where the IAT sensor resides.

As for the closeout panels, I don't think that's the answer either...yes, it would help keep the hot air from the radiator from entering the front of the air box, but the issue here is that the intake tract where the IAT sensors are located heat up from the engine bay. That's what needs to be shielded here, not just the inlet.

[ACRucrazy]

That's not where the IAT sensor resides.

As for the closeout panels, I don't think that's the answer either...yes, it would help keep the hot air from the radiator from entering the front of the air box, but the issue here is that the intake tract where the IAT sensors are located heat up from the engine bay. That's what needs to be shielded here, not just the inlet.

Yea that was what I was getting at. The close out panels are forcing all the air into the radiator. And if its cold air going in, that means hot air coming out the back of the radiator heating up the intake tubes/airbox.

[Voice of Reason]

I have an IAT relocation kit on my daily driver G8, isn't something like in the following link what we need? It plugs in line to the integrated MAF housing and disables the IAT there, and then you relocate a new IAT farther up steam where it's not getting heat soaked. The only permenant alteration a person makes with this is drilling a hole for the new IAT location.

http://www.vectormotorsports.com/ind...mart&Itemid=28

[Voice of Reason]

Yea that was what I was getting at. The close out panels are forcing all the air into the radiator. And if its cold air going in, that means hot air coming out the back of the radiator heating up the intake tubes/airbox.

I'd love to see someone design a shield that directs all (or most) of the radiator heat out up through our heat extractor hoods. I think that's how the GT3-R Viper does it.

[ACRucrazy]

I have an IAT relocation kit on my daily driver G8, isn't something like in the following link what we need? It plugs in line to the integrated MAF housing and disables the IAT there, and then you relocate a new IAT farther up steam where it's not getting heat soaked. The only permenant alteration a person makes with this is drilling a hole for the new IAT location.

http://www.vectormotorsports.com/ind...mart&Itemid=28

I like this thread! It's something new and people are starting to think!

[Nine Ball]

That IAT relocation kit is exactly what we need. Two of them, in fact. Just need someone to find the sensor data and build them now.

[mjorgensen]

The cross brace under the sensors/tubes get wicked hot and radiates heat right under the sensors. We have a car in the shop we are doing headers and exhaust on. I think I will try and insulate this area and the underside of the air box since it is pretty thin material anyway.

The following infrared pictures were taken at the end of this sequence:

1. Ambient air temperature was 41F.

2. After 30 minutes of driving at 45 mph the displayed IAT was 71, that is normal for my car. That makes no sense for a car with a cold air inlet, but, it is usually plus 30 degrees over ambient.

3. The car idled for ten minutes, displayed IAT went to 93.

4. Shut the car down and waited five minutes, displayed IAT went to 125.

5. The following pictures were then taken.

The "+" sign is a marker and indicates the temp at that point. The straight line can be graphed, however, the three temps above the line are the min/mx/average. The lighter colors are hotter.


IR_00015.jpgIR_00016.jpgIR_00018.jpg

[Nine Ball]

Mark: Woodhouse IAT relocation kit. Do it

[FLATOUT]

I'm sure the Gen 4 guys would be interested as well

[Brian GTS]

I'm interested....

[Jack B]

Here is the temperature graph from one of the earlier ir pictures. The line is on top of the intake tube and runs from the throttle body to the front of the air box, it is obvious how much cooler the temps are at the front of the air box.

The two downward deviations are from the low emissivity of the band clamps and are meaningless.




Intake tube graph.jpg

[Shooter]

Why not connect a switch to run the fan/fans whenever you want.? Not a sure fix, but something you can use in the staging lanes. Might get some of that hot air out of there while idling. I know a lot of SRT Jeep guys used to do that.

BTW, the Gen V and Gen IV airbox look almost exactly alike to me. Next time I'm at Tomball Dodge I'll have to look.

[mjorgensen]

Mark: Woodhouse IAT relocation kit. Do it

Not sure if the plug are all universal are they Tony? Plus where would you put them and still have them behind the filter for protection that is not just as hot? I'm not sure about having them exposed all the time outside of it.