I know there was a discussion about this a while back, and I think someone answered it for me, but i am not sure.
On the L61 supercharged cars, we only have 1 IAT reading correct? As opposed to the LSJ's that get 2? And our IAT reading come from the TMAP, which reads the air after compression and after it has already gone through the intercooler cores right?
Edited 1 time(s). Last edited Tuesday, August 30, 2011 2:54 PM
Correct.
We only use IAT1, which is read by the TMAP (or like in my case, I used a threaded IAT in the manifold, and run my stock MAP off a boost referenced source)..either route, it's reading already compressed air, after passing the cores, and moving into the head.
So theoretically, when its 110 outside, 140 IAT readings are not that bad at all.
Our iat is the iat2 from the lsj. I still dont think the tmap iat reads right.
Wait overnight and just turn the key to on without starting the car and connect with the scanner. If the iat and ect temps are the same then your iat reads correctly, if not, you're like me and its a guessing game.
Edited 1 time(s). Last edited Tuesday, August 30, 2011 8:27 PM
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
I looked today when I got in the car, the IAT was 96.8 and the ECT was 98.6. I am guessing that less the 2* isnt a big deal. But I made a point to not go into boost today, and the car stayed below 130 IAT unless I was stopped at idle for a while, then they went up to about 140ish. The ECT however stayed at between 188 and 194 the entire time until I was at a red light for what seemed like 5-6 minutes right before the turn into my work parking lot.
Sweet. You wouldnt heat soak as much with an intake mani spacer.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Leafy (Club Jeffie FEA man) wrote:Our iat is the iat2 from the lsj. I still dont think the tmap iat reads right.
Wait overnight and just turn the key to on without starting the car and connect with the scanner. If the iat and ect temps are the same then your iat reads correctly, if not, you're like me and its a guessing game.
That makes no sense to me. Coolant (fluid) and metal/air is going to have different readings.
FU Tuning
yeah Leafy i was looking at them today on css.net seem like a lot of work though, when meth would keep things cool too. i bet the combo of both would be even better.
No Longer Screaming wrote:Leafy (Club Jeffie FEA man) wrote:Our iat is the iat2 from the lsj. I still dont think the tmap iat reads right.
Wait overnight and just turn the key to on without starting the car and connect with the scanner. If the iat and ect temps are the same then your iat reads correctly, if not, you're like me and its a guessing game.
That makes no sense to me. Coolant (fluid) and metal/air is going to have different readings.
Not when both of them have acclimated to the ambient air temperature. Once the car is running, oh yeah they better be different. But before starting the car after it has sat over night they should read the same temperature.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
EvoFire wrote:So theoretically, when its 110 outside, 140 IAT readings are not that bad at all.
This seems reasonable for idle or cruising. If this is after a long pull, you're doing quite well actually. According to Eaton, at 10 psi, the blower adds about 80*F to the ambient air. If you're only +30 you're doing great.
Wait so you're saying that two different things at the same temperature will read differently on a thermometer based on their composition? Here's a test, you need a normal thermometer and a surface thermometer. Put a piece of metal in a pot with water and boil the water. The water will be 212*F and so will the piece of metal. OR leave a glass of water on the counter next to a piece of metal for a couple hours and then measure their temperatures. Is basic principles of science.
Edited 1 time(s). Last edited Thursday, September 01, 2011 6:20 AM
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Lol when i was in school the princi
pal told me i should learn the princi
ples of science
sorry i had to!!
.
Took the freeway home tonight, at cruising speed, IATs got down to 129 with ambient temp of about 110....im pretty happy with that!!!
That's real damned close to where mine runs at as well. After a 2nd and 3rd gear pull to 7K yesterday the reading climbed up to 155 while seeing about 11.5psi.
Where is your air filter located?
No Longer Screaming wrote:Leafy (Club Jeffie FEA man) wrote:No Longer Screaming wrote:Leafy (Club Jeffie FEA man) wrote:Our iat is the iat2 from the lsj. I still dont think the tmap iat reads right.
Wait overnight and just turn the key to on without starting the car and connect with the scanner. If the iat and ect temps are the same then your iat reads correctly, if not, you're like me and its a guessing game.
That makes no sense to me. Coolant (fluid) and metal/air is going to have different readings.
Not when both of them have acclimated to the ambient air temperature. Once the car is running, oh yeah they better be different. But before starting the car after it has sat over night they should read the same temperature.
yeah I disagree.
hes right if your coolant has been sitting and CLIMATIZED it should give the same reading as ambient air its like whats heavier a tonne of Bricks or a Tonne of feathers. if we were talking volume or desity then his statement would be false but a climatized nuetral NONE running car both should be neutral within a few degrees
JBO since July 30, 2001
He said "after sitting overnight", which means, yes they will absolutely be the same. That's a completely cold start. Now, if the car has been sitting for five or ten minutes after being run at operating temperature and you do the same thing, who knows. The problem is, when you key on but don't start, you're getting a heat soaked reading from the aluminum manifold with no air or coolant running through it. IMO, as soon as you start the car and air starts moving, the IAT is inaccurate (high) to a small extent.
