Kodiak 100 ITT value disagree with SimConnect variable

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I have read through all possible topics here and couldn’t find a similar question so please accept my apologizes if this has been asked in the past already. If this is not the proper thread to post this question, please point me to the right direction. Thanks!

I’m trying to read the ITT value from the Kodiak 100 using SimConnect (SimVar name ‘TURB ENG ITT:1’) and/or FSUIPC (Offset 0x2038). According to the documentation this value is given in degrees Rankine and has to be converted to the unit required. Unfortunately the result of a conversion to degrees Celsius does not agree with the value indicated on the G1000 and I cannot figure out why.
The equation to convert a temperature given in degrees Rankine to degrees Celsius is as follows:
Temp °C = (Temp R° - 491.67) * 5/9

Here are some results of such a conversion, taken at different ITT temperatures (all values are rounded here to make it easier to read). The value in the first column is the value provided by SimConnect, the second column is the converted value as per the equation above. In brackets you can see the indicated ITT on the MFD of the G1000. I also tested with the default G1000, but the results are the same.

1104°R → 340°C (G1000: 488°C), Difference +148°
1251°R → 421°C (G1000: 524°C), Difference +103°
1390°R → 499°C (G1000: 557°C), Difference +58°
1551°R → 588°C (G1000: 597°C), Difference +9°

You might see that the difference becomes less the higher the Rankine temperature is.

Any ideas why this is and how to overcome?
Thanks very much!

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This is not the only value that is not correct. In many aircraft the devs fake the values displayed because they are unable to simulate the system properly. Either because they dont know how to do it or because the state of the sim does not allow a proper simulation.

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A lot of Developers use their own variables for engine simulation, so just use the LVARs from the Kodiak. You can see the LVARs in DEV Mode - Windows/Behavior - Local Variables.

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Thanks very much @OldBoldPilot811 and @JayDee6281 for your replies.

I didn’t know that :worried: so a special thank you for this information. It helps a lot. Now I can see the ITT value and I only have to figure out how to read these LVARs via FSUIPC. I’m not yet familiar with this LVAR stuff but I’m keen to get into that.

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To save having to convert you can specify the simconnect type to be the units you want. There is a list of all the available units on one of the SDK pages. No idea why they went with Rankine as the default but it’s left over from FSX.