I want to install an electric temperature gauge.
Any suggestions? What do I need?

 

Your nick seems to be Polish related, doesn't it?
You need a gauge, an adapter to fit the sensor and to do some wiring.

adapter-> http://www.dabtuner.pl/image_func.ph...g&maxwidth=220

 

Why?
Every car already comes with one.

 

Its nice to know exactly what temp the car is running at, not just by little dots on the dash that say whether its hot or cold. For example my temp gauge will get in H zone alot but never has over heated. If i had a gauge i could monitor it and see if it actually is operating at hot levels.

 

Use the sensor that Honda provided with the car. Then run a wire to your external gauge. Read the instructions that come with the gauge and you will know what to do.

Also, if you are keen enough with a car, buy a megasquirt stand alone engine management unit. You can do anything with that. And you can monitor and log everything with a laptop if you want.