IAT Gauge Question

[Tommy Gun]

I asked questions a while back about getting an IAT gauge and ended up getting one like this that was reccomended...

http://www.egauges.com/vdo_ind.asp?Type=Digital_Amp_Temp&Series=Cy_Blue_Black&PN=A223E361Y

I just don't get the sensor pickup?


This is a pic of what they call the sensor. (yes it's just a connector)


.

http://i670.photobucket.com/albums/vv61/fastestshelby2/Secret%20Secret%20Santa/DSC09319.jpg

http://i670.photobucket.com/albums/vv61/fastestshelby2/Secret%20Secret%20Santa/DSC09318.jpg


And it in just stuck into the Intake tube....


http://i670.photobucket.com/albums/vv61/fastestshelby2/Secret%20Secret%20Santa/DSC09320.jpg


I just don't get how accurate that can be?

Does anyone understand how that could be?

It would seem to me that the wire going to it could get hot and give false readings although I covered it the best I could.


:waiting:

.

[Joe G]

Theres probably a thermistor between the connector and the wire going up to the sensor.

A connector by itself wouldn't do anything. There needs to be something inline that changes resistance dependent on temperature. That's were the thermistor is used. They can be very small. Might be under the heat shrink.

The thermostat sensor on our kero stove is about the size of the head of a wooden match (and that's with small vinyl cover over it). Possibly the 'connector' end is just so it can be conveniently mounted with a screw -- it may also complete the circuit to ground (depending on how the circuit is designed -- see if the instructions say it must be grounded or not). There has to be a thermistor under there ...they can be quite accurate.

[Tommy Gun]

That doesn't look like any sensor I've seen.


I know.

I called them and they just say it picks up the heat.

I just don't get it?

[tekheavy]

I know.

I called them and they just say it picks up the heat.

I just don't get it?

Theres probably a thermistor between the connector and the wire going up to the sensor.

[Tommy Gun]

Theres probably a thermistor between the connector and the wire going up to the sensor.


Okay, had to look that one up.

http://en.wikipedia.org/wiki/Thermistor

It really just looks like a connector then the wire.

Do you know how small such a device might be?







I just asked Tek a technical question. :groan:

.

[tekheavy]

Okay, had to look that one up.

http://en.wikipedia.org/wiki/Thermistor

It really just looks like a connector then the wire.

Do you know how small such a device might be?







I just asked Tek a technical question. :groan:

.

A connector by itself wouldn't do anything. There needs to be something inline that changes resistance dependent on temperature. That's were the thermistor is used. They can be very small. Might be under the heat shrink.

[tekheavy]

I just asked Tek a technical question. :groan:

.

I'm an electrical technician, dufus. :boink:

[Joe G]

Theres probably a thermistor between the connector and the wire going up to the sensor.

:wow2:

You sounded smart there!

[Tommy Gun]

A connector by itself wouldn't do anything. There needs to be something inline that changes resistance dependent on temperature. That's were the thermistor is used. They can be very small. Might be under the heat shrink.


Okay, thanks.

I see what it does once completely hooked up, just seems weird to me.

.

[Tommy Gun]

I'm an electrical technician, dufus. :boink:



Sorry, I didn't read the occupation thread. :grin:

[Joe G]

I'm an electrical technician, dufus. :boink:

:wow2:

I didn't know you even knew how to spell that.







:hiding:

[Tommy Gun]

:wow2:

You sounded smart there!


:hey2: Tek's my best friend back off.

.

[Joe G]

:hey2: Tek's my best friend back off.

.

WHAT?!?!?





:kickrock:

[dwattsup]

Looks awesome!

[Tommy Gun]

Looks awesome!



Not yet, just a bunch of wires. LOL


4048

[dwattsup]

So it's an internal air temp gauge? It looked pretty cool on the website. That so called sensor looks like a ground connector.

[tekheavy]

:hey2: Tek's my best friend back off.

.

:faint:

[Joe G]

Not yet, just a bunch of wires. LOL


4048

You need to clean all the dirt from behind those gauges! :cop2:

[Tommy Gun]

So it's an internal air temp gauge? It looked pretty cool on the website. That so called sensor looks like a ground connector.



They call it an Amplifier Temp Gauge.

That is what I've been told to use for an Inlet Air Temp gauge since I don't believe the car has any such connection from the factory.

.

[Tommy Gun]

You need to clean all the dirt from behind those gauges! :cop2:


It's a track only car now, it doesn't get cleaned much. LOL

[68fastback]

I think Tek nailed it.

The thermostat sensor on our kero stove is about the size of the head of a wooden match (and that's with small vinyl cover over it). Possibly the 'connector' end is just so it can be conveniently mounted with a screw -- it may also complete the circuit to ground (depending on how the circuit is designed -- see if the instructions say it must be grounded or not). There has to be a thermistor under there ...they can be quite accurate.

[Tommy Gun]

I think Tek nailed it.

The thermostat sensor on our kero stove is about the size of the head of a wooden match (and that's with small vinyl cover over it). Possibly the 'connector' end is just so it can be conveniently mounted with a screw -- it may also complete the circuit to ground (depending on how the circuit is designed -- see if the instructions say it must be grounded or not). There has to be a thermistor under there ...they can be quite accurate.


Thanks.

It has a sensor wire and a ground wire coming out of it.

.

[68fastback]

ok, so that eyelet may just be for 'convenience' ...the thermistor itself is tough and could just dangle wherever so putting that eyelet on if seems odd if it serves no functinal purpose. Here's a pic of the vinyl-covered temp sensor I mentioned -- pretty small.

4051

[Tommy Gun]

ok, so that eyelet may just be for 'convenience' ...the thermistor itself is tough and could just dangle wherever so putting that eyelet on if seems odd if it serves no functinal purpose. Here's a pic of the vinyl-covered temp sensor I mentioned -- pretty small.

4051


They had told me I could bolt it in place, stick it in place or just lay it where need be.

So The connector has no other purpose.

.

[Tommy Gun]

Where's Tek?

I need him to confirm all this. LOL


.

[Joe G]

Theres probably a thermistor between the connector and the wire going up to the sensor.

A connector by itself wouldn't do anything. There needs to be something inline that changes resistance dependent on temperature. That's were the thermistor is used. They can be very small. Might be under the heat shrink.

The thermostat sensor on our kero stove is about the size of the head of a wooden match (and that's with small vinyl cover over it). Possibly the 'connector' end is just so it can be conveniently mounted with a screw -- it may also complete the circuit to ground (depending on how the circuit is designed -- see if the instructions say it must be grounded or not). There has to be a thermistor under there ...they can be quite accurate.


See... just like I said first. Jeeze! :nonono:

[Tommy Gun]

See... just like I said first. Jeeze! :nonono:


:wow2: You are smart....except....








.








.






this is a tech thread. :rant:

.

[68fastback]

They had told me I could bolt it in place, stick it in place or just lay it where need be.

So The connector has no other purpose.

.

Seems that way...

...should be able to put it anywhere that won't affect airflow pattern for the MAF sensor -- I think you had it downstream which should be ok ...but it looks like it's right in front of the TB butterflies (??) which might create a little turbulence (less airflow/HP) there? ...can't tell, just mentioning as a consideration ...maybe birdy has some thoughts?

[Alloy Dave]

Theres probably a thermistor between the connector and the wire going up to the sensor.

A connector by itself wouldn't do anything. There needs to be something inline that changes resistance dependent on temperature. That's were the thermistor is used. They can be very small. Might be under the heat shrink.

The thermostat sensor on our kero stove is about the size of the head of a wooden match (and that's with small vinyl cover over it). Possibly the 'connector' end is just so it can be conveniently mounted with a screw -- it may also complete the circuit to ground (depending on how the circuit is designed -- see if the instructions say it must be grounded or not). There has to be a thermistor under there ...they can be quite accurate.

TG, you can check this.

Take the entire wire off the car....
allow it to come to room temperature
Use an ohmmeter to check the resistance

Heat up the end somehow
Check resistance again
If the resistance changed, you have the answer

My guess is that the change in resistance may be very small, may need a very accurate meter

[Tommy Gun]

Seems that way...

...should be able to put it anywhere that won't affect airflow pattern for the MAF sensor -- I think you had it downstream which should be ok ...but it looks like it's right in front of the TB butterflies (??) which might create a little turbulence (less airflow/HP) there? ...can't tell, just mentioning as a consideration ...maybe birdy has some thoughts?


It is a couple inches in front of the butterflies.

.

[tekheavy]

TG, you can check this.

Take the entire wire off the car....
allow it to come to room temperature
Use an ohmmeter to check the resistance

Heat up the end somehow
Check resistance again
If the resistance changed, you have the answer

My guess is that the change in resistance may be very small, may need a very accurate meter

He may not be able to get to the other end of the wire without having to cut through the insulation which he might not want to do. Although he could just take a pin and poke it through the insulation to run the test.

[68fastback]

It is a couple inches in front of the butterflies.

.

...probably not a great spot ...I think the TB would like to see nice laminar-flow air if possible. Any turbulence has to reduce flow a bit. Not sure where might be better ...not familiar with the plumbing on yours. Is your mass air meter far forward or right in that tube? ... maybe there are other options.

[Tommy Gun]

He may not be able to get to the other end of the wire without having to cut through the insulation which he might not want to do. Although he could just take a pin and poke it through the insulation to run the test.


IAT and water gauge are both hooked up and installed in the car....too hard to remove.

When I connected power today the IAT gauge showed 47 degrees. I assume that was the temp outside.

I started it for 5 minutes, ran around the block (1 mile) and park w/ it running and it got to 59 degrees.

Water temp was at 185 degrees, so I am assuming for now that the IAT is working.


Now to find out what is normal for IAT temps? 110-115 degrees? ???

[Tommy Gun]

...probably not a great spot ...I think the TB would like to see nice laminar-flow air if possible. Any turbulence has to reduce flow a bit. Not sure where might be better ...not familiar with the plumbing on yours. Is your mass air meter far forward or right in that tube? ... maybe there are other options.


http://i670.photobucket.com/albums/vv61/fastestshelby2/2002%20INTAKE/valve20001.jpg

[Joe G]

:wow2:


Nice drawing.

[Tommy Gun]

:uwelcome:

.

[Alloy Dave]

IAT and water gauge are both hooked up and installed in the car....too hard to remove.

When I connected power today the IAT gauge showed 47 degrees. I assume that was the temp outside.

I started it for 5 minutes, ran around the block (1 mile) and park w/ it running and it got to 59 degrees.

Water temp was at 185 degrees, so I am assuming for now that the IAT is working.


Now to find out what is normal for IAT temps? 110-115 degrees? ???
Dan or George can correct me if I'm wrong, but I think you'll commonly see discussions around two diff IATs. IAT_1 and IAT_2. IAT_1 is before the S/C and should read ambient. IAT_2 is after the S/C, and since the air is compressed it will be hotter. If yours is right in front of the TB, I'd assume that you should call that IAT_2.

The only reason I point this out is that if you do a Google search and see people saying IAT should be whatever ambient is, I didn't want you to be confused. I am not sure what "typical" IAT_2 would be....but the cooler the better. I'm thinking around 30-40 degrees over ambient would be very good after the car is entirely heated up and you've run some boost.

Dan/George, do I have that right?

[Alloy Dave]

Bill, just found this link.

http://www.svtperformance.com/forums/terminator-talk-229/414826-difference-temp-your-iat1-compared-iat2-post-your-findings.html

[Joe G]

Bill, just found this link.

http://www.svtperformance.com/forums/terminator-talk-229/414826-difference-temp-your-iat1-compared-iat2-post-your-findings.html

:wow2:


4065

[Alloy Dave]

As carnut would say, even a blind squirrel ....

®EVAD

[68fastback]

You're correct, Dave.

I think you'd want to know both (IAT1 and IAT2) to gauge how effective the cooler is but, if only one, IAT2 would be more usefull relative to tuning/timing, etc. I think there must already be an IAT2 somewhere in the lower intake since the calibration needs that. If so, then this sensor is either so the driver has a visual of IAT1 or 2.

If looking for a visual of IAT2, in TG's diagram just after (downstream of) the MAF housing would be good, I think. If that's not practical, then just after the cooler. I'd avoid just before the MAF to eliminate any possibility of turbulence affecting the air pattern in MAF tube since that would affect mass-air readings, A/Fs, and most everything else in the calibration too.

If data-logging (vs a visual for the driver) then I'd want to log the actual IAT2 (which might be the original NA IAT1) the calibration is seeing, using an onboard logger/PC, etc.

TG, what is the intended use for this sensor? maybe birdy or blackshelby have some advice based on what you're trying to accomplish.

[Tommy Gun]

Dan or George can correct me if I'm wrong, but I think you'll commonly see discussions around two diff IATs. IAT_1 and IAT_2. IAT_1 is before the S/C and should read ambient. IAT_2 is after the S/C, and since the air is compressed it will be hotter. If yours is right in front of the TB, I'd assume that you should call that IAT_2.

The only reason I point this out is that if you do a Google search and see people saying IAT should be whatever ambient is, I didn't want you to be confused. I am not sure what "typical" IAT_2 would be....but the cooler the better. I'm thinking around 30-40 degrees over ambient would be very good after the car is entirely heated up and you've run some boost.

Dan/George, do I have that right?

I understand the IAT1 and IAT2's, just didn't know what was normal.

Thanks for the link that clears it up pretty well.

[Tommy Gun]

You're correct, Dave.

I think you'd want to know both (IAT1 and IAT2) to gauge how effective the cooler is but, if only one, IAT2 would be more usefull relative to tuning/timing, etc. I think there must already be an IAT2 somewhere in the lower intake since the calibration needs that. If so, then this sensor is either so the driver has a visual of IAT1 or 2.

If looking for a visual of IAT2, in TG's diagram just after (downstream of) the MAF housing would be good, I think. If that's not practical, then just after the cooler. I'd avoid just before the MAF to eliminate any possibility of turbulence affecting the air pattern in MAF tube since that would affect mass-air readings, A/Fs, and most everything else in the calibration too.

If data-logging (vs a visual for the driver) then I'd want to log the actual IAT2 (which might be the original NA IAT1) the calibration is seeing, using an onboard logger/PC, etc.

TG, what is the intended use for this sensor? maybe birdy or blackshelby have some advice based on what you're trying to accomplish.



My main purpose on that gauge it to get a norm, then I can keep an eye on it to make sure nothing is out of whack.

Like trash blocking my intake or intercooler, etc.

[Alloy Dave]

My main purpose on that gauge it to get a norm, then I can keep an eye on it to make sure nothing is out of whack.

Like trash blocking my intake or intercooler, etc.

I'd think you'd want an A/F gauge or delta-P gauge for that...but ok.

IMO if any "trash" is in the duct past your air filter, you got bigger problems than knowing it's there....the only real place it could come from is the S/C pieces...and that would be bad.

[68fastback]

My main purpose on that gauge it to get a norm, then I can keep an eye on it to make sure nothing is out of whack.

Like trash blocking my intake or intercooler, etc.

So sounds like a visual IAT2 ...considerations in post 41 ...after the MAF or after the HE (intercooler)?


I'd think you'd want an A/F gauge or delta-P gauge for that...but ok.

IMO if any "trash" is in the duct past your air filter, you got bigger problems than knowing it's there....the only real place it could come from is the S/C pieces...and that would be bad.

I think TG means 'on' the HE (intercooler), etc ...at the track there can be blowing paper/debris, etc that can block the face of the HE or get in intake to the centrifugal.

Is that what you meant, Bill?

---

Btw, centriffugals act very different from FD SCs. If a centrifugal's inlet flow gets blocked the energy consumption (belt load) goes *down* (not up like a FD SC since the centrifugal impeller just happily spins the more stagnant air). A blocked FD SC consumes more HP (belt load goes way up as does heat) if restricted. A centrifugal has to 'engage' air flow to consume energy; and FD SC can consume lots of energy with little air flow.

[Tommy Gun]

Yes I have an air-to-air intercooler just behind the bumper face.

I've seen guys at the track get plastic bags blocking part of there air filter that is in the fender like mine.

When I originally asked about what 3-4 type gauges I should put on the car, the popular answers were oil pressure, water temp, boost, and IAT gauge. So that is what I got.

I also have an easier to see speedometer gauge. All the gauges also have memory so I can check them after a run.

[Birdman]

Dan or George can correct me if I'm wrong, but I think you'll commonly see discussions around two diff IATs. IAT_1 and IAT_2. IAT_1 is before the S/C and should read ambient. IAT_2 is after the S/C, and since the air is compressed it will be hotter. If yours is right in front of the TB, I'd assume that you should call that IAT_2.

The only reason I point this out is that if you do a Google search and see people saying IAT should be whatever ambient is, I didn't want you to be confused. I am not sure what "typical" IAT_2 would be....but the cooler the better. I'm thinking around 30-40 degrees over ambient would be very good after the car is entirely heated up and you've run some boost.

Dan/George, do I have that right?

Yes you are correct Dave.

Downstream IAT's should really not be much more than 15-30* above ambient if the IC system is working properly. You will see peaks of 30-50* after full throttle runs in traffic but that should quickly drop when back down while out in open air driving if the IC is doing it's job.

That said in order to get proper readings of IC efficency your IAT probe should be installed after the SC somewhere in the lower intake path before the air enters the combustion chamber.

[Tommy Gun]

That said in order to get proper readings of IC efficency your IAT probe should be installed after the SC somewhere in the lower intake path before the air enters the combustion chamber.



So it should be good where it's at?

.

[68fastback]

Ideally it hould be where your current IAT2 is in the lower intake (which is likely the original IAT sensor from when the car was NA).

[Alloy Dave]

So sounds like a visual IAT2 ...considerations in post 41 ...after the MAF or after the HE (intercooler)?



I think TG means 'on' the HE (intercooler), etc ...at the track there can be blowing paper/debris, etc that can block the face of the HE or get in intake to the centrifugal.

Is that what you meant, Bill?

---

Btw, centriffugals act very different from FD SCs. If a centrifugal's inlet flow gets blocked the energy consumption (belt load) goes *down* (not up like a FD SC since the centrifugal impeller just happily spins the more stagnant air). A blocked FD SC consumes more HP (belt load goes way up as does heat) if restricted. A centrifugal has to 'engage' air flow to consume energy; and FD SC can consume lots of energy with little air flow.
Oh.


As Emily Latella used to say...nevermind.

[Tommy Gun]

Ideally it hould be where your current IAT2 is in the lower intake (which is likely the original IAT sensor from when the car was NA).


I didn't even know the car had a IAT sensor?

Don't know where it would be?



My boost gauge finally came in, hope I have a place in the manifold for the sensor. :banghead:

I take it it can be anywhere below the TB?

.

[Joe G]

Ummm... you may want to rework some of this new wiring, TG. All these new gauges really made a mess. :yikes:



http://carphotos.cardomain.com/ride_images/2/4443/1221/23605610005_large.jpg

[Tommy Gun]

You have no idea. :nonono:



:lol:

[Alloy Dave]

You have no idea. :nonono:



:lol:

4093

[Tommy Gun]

:hey2: You been under my dash?????

[68fastback]

I didn't even know the car had a IAT sensor?

Don't know where it would be?



My boost gauge finally came in, hope I have a place in the manifold for the sensor. :banghead:

I take it it can be anywhere below the TB?

.

On the NA car I would expect it to be in the lower intake, but I did some searches and seems that 2002 GT had it in a rubber 'grommet' just downstream of the MAF (which is where I was suggesting in post-41 -lol). I did some parts lookup and it should be in a small twist-lock plastic fitting with a couple wires coming out of it. (maybe that's the one for the MAF and threre's another one in the lower intake? -dunno). I see Brenspeed sells an IAT relocation kit (http://www.brenspeed.com/breniatrelocation.html)to move the sensor into the intake manifold runner -- I'm guessing for better acuracy ...maybe the stock 02 GT really does have it just after the MAF.

[Tommy Gun]

I'll get some pics tomorrow.

I do have something in the tube about 12" before the TB.

Looks somewhat like....

4095

[Tommy Gun]

Okay got all the gauges in. :grin:


Here is what may be the factory IAT2 ?


http://i670.photobucket.com/albums/vv61/fastestshelby2/2002%20INTAKE/DSC09338.jpg



Here is where I have it. New IAT2 in upper left and factory in lower right.


http://i670.photobucket.com/albums/vv61/fastestshelby2/2002%20INTAKE/DSC09339.jpg



My new boost gauge sensor...

http://i670.photobucket.com/albums/vv61/fastestshelby2/2002%20INTAKE/DSC09337.jpg



These are the gauges installed.


http://i670.photobucket.com/albums/vv61/fastestshelby2/2002%20INTAKE/DSC09342.jpg




:crazy:

[Joe G]

:wow2:

Lots of new fancy gauges!

[Tommy Gun]

I got bored. :rofl3:




Actually.....


Since Mr. G couldn't get Cyberdyne gauges for me :shades: I ordered elsewhere....on Oct 29

Just got my last gauge yesterday!!!!! :nonono:

Terrible service. I've called them twice a week since just before Christmas.

It was always "they'll be sent out in a couple days" :blahblah:




:gun:

.

[Joe G]

Actually.....


Since Mr. G couldn't get Cyberdyne gauges for me :shades: I ordered elsewhere....on Oct 29

Just got my last gauge yesterday!!!!! :nonono:

Terrible service. I've called them twice a week since just before Christmas.

It was always "they'll be sent out in a couple days" :blahblah:




:gun:

.

I COULD get them, just not at the price you found.




See... price isn't always king.

Even your Torco didn't take 3 months. :haha:

[The Bone]

Looks like you got it all figured out gauges look good lots of wires you say. Didn't look that hard on TV.

[Tommy Gun]

:doh2: I thought you said you couldn't get those? :nonono:


I'm looking for the PM. :sherriff:

.

[Tommy Gun]

Looks like you got it all figured out gauges look good lots of wires you say. Didn't look that hard on TV.


Lots of wires.

I take my time working on the car so I don't have to re-do anything later.

[68fastback]

Very cool, Bill!

Possibly this would be a good spot for the new-gauge IAT sensor?

4115

[Joe G]

Very cool, Bill!

Possibly this would be a good spot for the new-gauge IAT sensor?

4115

That's what I was thinking... as far from the TB as possible.

[Tommy Gun]

Very cool, Bill!

Possibly this would be a good spot for the new-gauge IAT sensor?

4115


Originally I was going to put it there or one lower, but...when I bought the used S/C from my mechanic he had re-painted those tubes before installing the parts and the hoses are stuck pretty good to them.

So instead of breaking the seal and scratching up the tubes I put it where it is now.

When I have a little more time I may try to move it.

.

[Gr8snkbite]

Originally I was going to put it there or one lower, but...when I bought the used S/C from my mechanic he had re-painted those tubes before installing the parts and the hoses are stuck pretty good to them.

So instead of breaking the seal and scratching up the tubes I put it where it is now.

When I have a little more time I may try to move it.

.

see post 64......:doh2:

[Gr8snkbite]

:sofa:

[Tommy Gun]

see post 64......:doh2:


I thought it was placed properly.

Dan has since changed my mind.

Sometimes things just happen.


Oh, and :biteme:

.

[tekheavy]

:wow2:

[Birdman]

Originally I was going to put it there or one lower, but...when I bought the used S/C from my mechanic he had re-painted those tubes before installing the parts and the hoses are stuck pretty good to them.

So instead of breaking the seal and scratching up the tubes I put it where it is now.

When I have a little more time I may try to move it.

.

Quitter...

[Joe G]

Quitter...

:goodpost:









:giggle:

[68fastback]

:rofl:

[Birdman]

:grin:

[Tommy Gun]

:gun:

[tekheavy]

:wow2:

[The Bone]

To avoid scratching the tubes if you decide to remove the hose just rap the tube with blue masking tape then over the top of that wrap with duct tape and that way you won't scratch the paint. The blue tape will keep from damaging the paint. Duct tape will stick to paint and will probably damage it. So use the blue tape first.

[Tommy Gun]

Thanks Art. :wtg:

.

[Gr8snkbite]

TG are smart......





















NOT.....:tease2: