Hottest stock thermostat. If your car is lead free this is the one to use because the fuel needs higher temperatures to burn properly and provide best power and performance. Fitted from 1990 on as standard on 1275cc.
The lowest thermostat available is 74 degrees and should be the lowest one considered - 82 degrees is a much better choice with an 88 degree alternative for winter driving and those with economy as the main consideration.
The higher temperature the more thermally efficient the engine becomes. It is possible to run thermostats with the troublesome bypass hose blanked off by drilling 4-6 holes 1/8" in size around the periphery of the thermostat.