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Charge temp is what the fueling algorithm uses so It wouldn't be a representation of the compressed charge, which would be closer to 200-300 degrees C before ignition. I think it would be closer to the air temp as it is entering the intake port.

So out of curiosity I asked chatGPT. Here's what it said:

"In an EFI (Electronic Fuel Injection) system, the charge temperature is the temperature of the air/fuel mixture just before it enters the combustion chamber, while the intake air temperature is the temperature of the ambient air that is drawn into the engine's intake system.

The charge temperature is affected by several factors, including the temperature and pressure of the intake air, the efficiency of the air intake and compression process, and the heat generated by the engine. In general, increasing the intake air temperature can result in a higher charge temperature, which can affect the engine's performance and efficiency.

However, most EFI systems use sensors to measure the intake air temperature and adjust the fuel injection and ignition timing accordingly to compensate for the temperature changes. The engine control module (ECM) uses this information to calculate the ideal air/fuel ratio and ignition timing for optimal engine performance, taking into account the changes in charge temperature caused by the intake air temperature.

Therefore, while there is a relationship between the intake air temperature and the charge temperature in an EFI system, the system is designed to adjust the fuel injection and ignition timing to maintain optimal engine performance regardless of the intake air temperature."

I also asked it how hot the charge is before ignition:

"In a typical gasoline engine, the compression ratio is around 10:1 to 12:1, which means that the air-fuel mixture is compressed to one-tenth or one-twelfth of its original volume before ignition. Assuming ambient air temperature of 25°C, the compression of the air-fuel mixture to 10:1 ratio would result in an increase in temperature to approximately 250°C (which is about 523K) before ignition. Similarly, if the compression ratio is increased to 12:1, the temperature before ignition would increase to around 300°C (which is about 573K)."

I would imagine that the charge temperature on a L67 would be higher than a n/a V6. On our L67 I'm seeing about 60°C in the LIM from the MAT sensor once everything is up to temp and we are just cruising down the motorway (ambient temps about mid twenties). Our L67 runs a 3.2" pulley with all the usual mods but no intercooling. A good CAI is a must.

Ok that has to be correct, because ive checked the code in 12p and it only calculates between MAT and CLT. There is no factor to compensate for compression on top of that in the code.

My setup is l67 with a blower swap
98 fuel
Intake air temp sensor in lower intake manifold.
Seeing around 85c at cruise and around 104deg c after a pull. Timing is pretty lazy have checked the plugs and looks like no signs of pinging etc

Ouch that is getting hot.

Immortality old m90 setup i had on standard boost
Has cold air and exhaust mods
Was seeing 78deg at cruise and up to 90deg after a pull.
Must just be location of my iat sensor

Where is it mounted? Just under the blower in the side of the runner for No1 cylinder? If so, same spot as ours is.

It's probably a bit cooler over here in NZ.

I've added another snorkel to the MACE CAI which seems to have dropped the intake temps quiet a bit.

Thats were its mounted. Have a 4 inch pipe from behind bumper feeding the factory airbox thats sealed of from any engine bay heat.

Yup, about the same.