When it comes to rotaries, preventative measures and precautions are your best friends.
Ensure your oil is topped up,
Check your coolant level, the coolant sensor is known to fail and light will illuminate in ur dash

on your next maintenance get your coolant hoses inspected, its best to replace them as they become weak over the years and may leak at anytime.

Also get your alternator belt inspected, mine snapped on the highway at 120km and car overheated in seconds.

On the hot days don't rev it too much.

Your best bet is to always keep an eye on the temperature needle, the moment it moves from the middle shut the ignition down let the car come to stop.. pop the hood let things cool down.

If money is no object, then you can get a remedy waterpump and thermostat they help alot, also get kit to have your fan kick on earlier.

Actually i found this for you.. Read this thread 04Green did a great job of putting this togheter;

https://www.rx8club.com/new-member-f...8/#post3666147

 

I agree with all but this statement "On the hot days don't rev it too much.". If your coolant system is working and properly maintained, outdoor air temperature will not alter the cooling capability of the engine. Heat transfer is a result of three things and it's dominated by overall surface area A (that isn't changing except if your radiator fins are covered in mud or are all bent), fouling (that affects the coefficient U in the equation below), and delta T (temperature difference). Cars are designed with a U and A to manage the delta T such that the heat transfer can maintain the engine side temperature at a constant. It does so by restricting flow to the A (area) called the radiator.

Q = U*A*(Tcar - T outside)

Q = heat transferred
U = overall heat transfer ocoefficient = f(fouling, coolant quality, flow)
Tcar = set by manuafcturer
Toutside = variable

Ed

 

^ This.