Air intake temp sensor location

[baz]

I'm running speedshop manifolds like these



I was thinking of using the port bottom left of this pic for my air temp sensor.  It would need to stick out inside the manifold so I'm thinking maybe it's a bad idea as it will disturb air flow. Can anyone tell me if it's gonna be better somewhere else other than here? My air filters don't provide any simple alternative without welding or brazing a bung on top.

[Martin S.]

It's not too important. More critical on turbo engines as they can detonate more easily with a too-hot intake air temp, hence the desirability for an inter cooler. If your motor is N/A, then the air will not be much hotter in the manifold compared to the air cleaner.

Here is what Electromotive recommends:

"Install the MAT sensor in an area that is representative of the air temperature entering the engine. If it is mounted directly in the intake manifold (particularly in aluminum and iron manifolds), it may be getting a slightly warmer reading than the actual air temperature due to the conduction of heat through the manifold and the radiation of heat onto the sensor tip. It is sometimes better to install the sensor upstream a bit, particularly if the air intake (or filter box) is made of a material that does not conduct heat very well (like plastic). This will give the MAT sensor a more appropriate reading for intake air temperature."

[baz]

There's 6.5 inches between the port and base of manifolds so hopefully heat sink won't be much of an issue. I guess a little sensor sticking out inside won't hurt much either.

[Martin S.]

On bug engines you would not want to read the heat from the head if the head is close enough to the sensor to interfere. Mine is in the manifold too, but since the engine has a single TB the sensor is mounted in the center, well away from the heat of the heads.