I cant recall specifics now,but i asked for the lower opening temp one of the two that the guy at Auto pro had in the shop.
Looks like i'll have to try take the Thermostat out again an test it correctly, or I could just leave the Thermostat out?
I dunno exactly what the problem is but I know years ago when I first fitted the AU Fans and they kicked on,the Temp use to absolutely rocket downwards!! but like today they whirled away full rip for about 2 mins and the temp had only gone down 5 Degrees!!?????.
Unfortunately I have no fan controller yet......,they just stay off and when my temp guage shows 95 degrees the fans kick on then kick back off ( or use to) when the temp was back down at 70 or so but as I said even using no Fan Controller the fans use to make the temp soar down!.
In my opinion 5°C in two minutes is not bad considering the temperatures in Perth lately. What was the ambient temperature at the time?
You need to know what temperature the thermostat is designed for. The standard thermostat should be trying to maintain a temperature of around 83 °C. In theory it should be impossible for a cooling system to cool the engine below the thermostat temperature. You can not expect the fans to bring it back down to 70 °C with a 83 °C. thermostat.
I would have the thermo fans kicking in well before 95 °C if the engine will normally run at 83 °C.
A high flow thermostat like the Tridon TT2000-180 will help with water flow.
You should be able to determine at what temperature the thermostat is opening by running the engine from cold and seeing at what point the temperature stabilizes and the top hose gets warm.
The infra red temperature guns make diagnosing the system a lot easier.