Norm IAT'S

Sep 10, 2008
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Morehead City, North Carolina
Othrgrl and I were out logging my truck the other evening with ambient air temp around 60 degrees with IAT's reading 109 at idle. That sounds pretty high. Trying to get an idea of what "normal" IAT's you guys have seen. Looking into getting a banks/super scoop....
 

MMLMM

Tunergeek
Mar 2, 2008
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Reno, NV
www.dyncal.com
Was that IAT or IAT2?

IAT at idle should be closest to ambient temp. I was playing around tonight and outside temp was 51°F and IAT was right avg around 60°F

That sounds very high, even if it was IAT2 (after intercooler) it would still be pretty high at idle....

What would you guess the underhood temp to be?
 

LarryJewell

Back with his honey :)
Jan 21, 2007
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San Angelo
the higher the ambient temps the more difference between the ambient and IAT's, with ambient around 60* my IAT is normally within 10-15* at idle depending on how hard i'm pushing the truck, this is with the Banks Super Scoop
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
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ZEPHYRHILLS, FL
Mine would run around 120-150 at idle before I built the shield for the air filter. After putting in the shield so that the majority of the air comes from under the headlight my IAT's are within 10-15 degrees of ambient all the time. This is obviously the IAT from the MAF sensor as I have an 01. I know the LBz reads higher, but that is from at the actual engine intake when I was reading it.
 

McRat

Diesel Hotrodder
Aug 2, 2006
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Norco CA
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Idle is not a good indicator. You need to be moving at least a couple mph to make sense of the reading.

Sometimes a Corvette will read upwards of 150deg IAT at a stop, yet ambient on the freeway. It depends on where hot air rises to, and what is around to radiate heat into the IAT sensor.
 

McRat

Diesel Hotrodder
Aug 2, 2006
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Norco CA
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The only real concern is for staging or instant throttle response from a stop.

If an IAT table alters the fuel or timing with a false high reading at a stop, it takes time for the temp to change and will affect performance.

Normal procedure for racing tunes is to make sure IAT tables have nothing in them that could alter fuel or timing.