IAT Temps for PD Blowers

[Obsol3te]

This is relating to PD supercharger IAT's my friend. It's also been tested and known that the MAF built in IAT Sensor is not fast reacting sensor and can take up to 10 seconds to catchup. This was tested by Dept of Boost against a very accurate and fast reacting thermo coupn sensor system.

KB has their own sensor, so it should be accurate correct?

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[Roh92cp]

KB has their own sensor, so it should be accurate correct?

All the PD systems use a second AIT2 sensor like you have in your picture. The point your missing is none of them have assigned a PID or correct transfer function to display that data on the dash or with Ngauge or SCT or other other OBD scanners. The AIT2 sensor in these kits is used in the calibration to adjust timing according to the delta temps from IAT1 (inlet MAF) to the IAT2 (post compressor) it is not however been assigned a PID to be displayed in itself with a gauge or in the dash. To get a true IAT2 post compressor reading you need a standalone IAT2 located sensor with its own gauge able to read that sensor.

 

[zaquhree]

All the PD systems use a second AIT2 sensor like you have in your picture. The point your missing is none of them have assigned a PID or correct transfer function to display that data on the dash or with Ngauge or SCT or other other OBD scanners. The AIT2 sensor in these kits is used in the calibration to adjust timing according to the delta temps from IAT1 (inlet MAF) to the IAT2 (post compressor) it is not however been assigned a PID to be displayed in itself with a gauge or in the dash. To get a true IAT2 post compressor reading you need a standalone IAT2 located sensor with its own gauge able to read that sensor.

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[Roh92cp]

The other thing that is being missed in all this, but has been mentioned once here is the IAT2 reading we are mostly seeing and talking about here are when the bypass valve is open and recirculating hot air. What would should be more concerned about is what the IAT2 is doing when the bypass is closed and throttle is open (in boost). This is when air is really moving through the system, pulling fresh ambient air into the system and this is what really matters, (IAT2's under full boost) not hot air being recirculated through the bypass valve.

My concern with getting accurate data from IAT2 under full boost conditions is having a IAT sensor that has the ability to react fast enough to the changing conditions. Most of the sensors have a lag time with the exception of the Thermo couple sensors. So even if someone was able to data log the IAT2 data it may not report the accurate temps because of sensor response delay.

 

[Bahndvr]

My IAT would get down to within 3 degrees of outside temperature but no closer.

 

[BMR Tech]

Here is a WOT 3rd gear pull to 7700~ish RPM.

Looks like my IAT2 climbs about 27 degrees on this pull in about 5.7 seconds.

Definitely not much of a delay here. It may look like it on the initial hit...but I think the fresh incoming air on the hit, and the boost heat - work at cancelling eachother out for a bit before IATs start to rise drastically.

I cannot recall, but looking at the date of this log...It was likely around 80 degrees out.

Pull starts at 111 IAT2 and at the top of the WOT pull, peaks at 138.

My tuner is pretty comfortable with this, and seems to think it is pretty accurate. Of course, nothing would beat a true TC sensor for monitoring.

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