You could measure the temperature of the cooling fluid with a aftermarket sensor+gauge, but as long as it's a analog gauge, and the wire-ing has to be done by yourself, the reading won't be that accurate.

If you have a type-K termocouple with a digital readout, there shouldn't be a big variation though: reading should be within 3 degrees accurate.

The question is: Why would you like to have a accurate readout of the cooling temperature, whereas the oil temp is much more important..

This will give you a nice indication:



but this will give you the best reading:




See conrad.de or equiv.

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