OAT vs. IAT: Linear or exponential?
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From: Dyess AFB, TX
OAT vs. IAT: Linear or exponential? I did a little tuning on my car this weekend and noticed my FIPK was sucking in 153* air while the outside air temp was around 85*. This is on a Z-28 which has no way of bringing in cool air at all with the FIPK. So I decided to make a new intake which consists of a 90* bend off the TB towards the driver side, over the PS pump, 45* down to the fuse box area, then another 45* to where the AIR pump used to be. I figured this would bring in much cooler air than the FIPK.
So now my question, is the relationship between OAT and IAT linear or exponential? Using my numbers above, we could say that IAT was ~70* above OAT that day. Would that hold true if the OAT was 40*? Or as you get cooler OATs, does the difference get smaller? Do the hotter temps cause a bigger gap between the two?
The reason I'm asking is when I try out my new intake, I'd like to know if it's actually working or not. If the OAT happens to be 100* when I test it, but the IAT is 160*, then I'd know it's working somewhat if there was a linear relationship between the two.
So now my question, is the relationship between OAT and IAT linear or exponential? Using my numbers above, we could say that IAT was ~70* above OAT that day. Would that hold true if the OAT was 40*? Or as you get cooler OATs, does the difference get smaller? Do the hotter temps cause a bigger gap between the two?
The reason I'm asking is when I try out my new intake, I'd like to know if it's actually working or not. If the OAT happens to be 100* when I test it, but the IAT is 160*, then I'd know it's working somewhat if there was a linear relationship between the two.
It's not an offset. It's a percentage.
It's also not a constant percentage. It will change depending on your driving habits due to heat-soak and insulation of various parts under the hood.
It's also not a constant percentage. It will change depending on your driving habits due to heat-soak and insulation of various parts under the hood.
Thread Starter
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From: Dyess AFB, TX
Originally Posted by white2001s10
It's not an offset. It's a percentage.
It's also not a constant percentage. It will change depending on your driving habits due to heat-soak and insulation of various parts under the hood.
It's also not a constant percentage. It will change depending on your driving habits due to heat-soak and insulation of various parts under the hood.
